diff --git a/extensions/qa-channel/src/channel-base.ts b/extensions/qa-channel/src/channel-base.ts
index 96a9caa416ec..70cf89b7dbe3 100644
--- a/extensions/qa-channel/src/channel-base.ts
+++ b/extensions/qa-channel/src/channel-base.ts
@@ -1,5 +1,4 @@
 // Qa Channel plugin module implements channel base behavior.
-import { getChatChannelMeta } from "openclaw/plugin-sdk/channel-plugin-common";
 import {
   listQaChannelAccountIds,
   resolveDefaultQaChannelAccountId,
@@ -13,15 +12,16 @@ import type { CoreConfig } from "./types.js";
 
 export const QA_CHANNEL_ID = "qa-channel" as const;
 
-export const qaChannelSetupMeta = { ...getChatChannelMeta(QA_CHANNEL_ID) };
+// qa-channel is synthetic and never in the bundled chat-meta catalog; it owns
+// its metadata instead of spreading a lookup that could only ever be undefined.
 export const qaChannelRuntimeMeta = {
-  ...qaChannelSetupMeta,
   id: QA_CHANNEL_ID,
   label: "QA Channel",
   selectionLabel: "QA Channel",
   docsPath: "/channels/qa-channel",
   blurb: "Synthetic QA channel for OpenClaw QA runs.",
 };
+export const qaChannelSetupMeta = qaChannelRuntimeMeta;
 
 type QaChannelPluginBase = Pick<
   ChannelPlugin<ResolvedQaChannelAccount>,
diff --git a/src/acp/control-plane/manager.turn-runner.ts b/src/acp/control-plane/manager.turn-runner.ts
index 80e338f9d78d..19b39c085522 100644
--- a/src/acp/control-plane/manager.turn-runner.ts
+++ b/src/acp/control-plane/manager.turn-runner.ts
@@ -1,5 +1,6 @@
 /** Runs ACP turns, failover, timeout cleanup, and detached-task progress mirroring. */
 import type { AcpRuntime, AcpRuntimeHandle } from "@openclaw/acp-core/runtime/types";
+import { expectDefined } from "@openclaw/normalization-core";
 import { logVerbose } from "../../globals.js";
 import {
   recordSessionHumanDirectMessage,
@@ -165,8 +166,7 @@ export async function runManagerTurn(params: {
   }
 
   try {
-    for (let backendIdx = 0; backendIdx < candidateBackends.length; backendIdx += 1) {
-      const currentBackend = candidateBackends[backendIdx];
+    for (const [backendIdx, currentBackend] of candidateBackends.entries()) {
       if (backendIdx > 0) {
         await params.runtimeHandles.close({
           sessionKey,
@@ -174,7 +174,10 @@ export async function runManagerTurn(params: {
         });
         logVerbose(
           `acp-manager: switching backend for ${sessionKey} from ${describeBackendCandidate(
-            candidateBackends[backendIdx - 1],
+            expectDefined(
+              candidateBackends[backendIdx - 1],
+              "candidate backends entry at backend idx 1",
+            ),
           )} to ${describeBackendCandidate(currentBackend)}`,
         );
       }
diff --git a/src/acp/translator.presentation.ts b/src/acp/translator.presentation.ts
index f946a1ce34fd..fc3710bebbd1 100644
--- a/src/acp/translator.presentation.ts
+++ b/src/acp/translator.presentation.ts
@@ -110,7 +110,7 @@ function formatThinkingLevelName(level: string): string {
     case "adaptive":
       return "Adaptive";
     default:
-      return level.length > 0 ? `${level[0].toUpperCase()}${level.slice(1)}` : "Unknown";
+      return level.length > 0 ? `${level.charAt(0).toUpperCase()}${level.slice(1)}` : "Unknown";
   }
 }
 
@@ -126,7 +126,7 @@ function formatConfigValueName(value: string): string {
     case "xhigh":
       return "Extra High";
     default:
-      return value.length > 0 ? `${value[0].toUpperCase()}${value.slice(1)}` : "Unknown";
+      return value.length > 0 ? `${value.charAt(0).toUpperCase()}${value.slice(1)}` : "Unknown";
   }
 }
 
diff --git a/src/agents/model-catalog.ts b/src/agents/model-catalog.ts
index 39760c7b3776..0faa0ec4ea8c 100644
--- a/src/agents/model-catalog.ts
+++ b/src/agents/model-catalog.ts
@@ -324,10 +324,11 @@ function mergeCatalogRouteVariants(
       collector.indexByKey.set(key, collector.entries.length - 1);
       continue;
     }
-    collector.entries[existingIndex] = overlayCatalogMetadata(
-      collector.entries[existingIndex],
-      entry,
-    );
+    const existingEntry = collector.entries[existingIndex];
+    if (existingEntry === undefined) {
+      continue;
+    }
+    collector.entries[existingIndex] = overlayCatalogMetadata(existingEntry, entry);
   }
 }
 
diff --git a/src/agents/provider-model-auth-source-plan.ts b/src/agents/provider-model-auth-source-plan.ts
index 05549b3c0d51..795947e4f14b 100644
--- a/src/agents/provider-model-auth-source-plan.ts
+++ b/src/agents/provider-model-auth-source-plan.ts
@@ -125,7 +125,10 @@ export function buildProviderModelAuthSourcePlan(params: {
   } else {
     const available = ordered.filter((profile) => profile.readiness !== "unavailable");
     if (available.length === 0) {
-      profiles = { kind: "all-unavailable", explicitOrder, first: ordered[0] };
+      const [firstOrdered] = ordered;
+      profiles = firstOrdered
+        ? { kind: "all-unavailable", explicitOrder, first: firstOrdered }
+        : { kind: "empty", explicitOrder };
     } else {
       const outsideCooldown = available.filter((profile) => profile.cooldown === "clear");
       if (outsideCooldown.length > 0) {
@@ -133,7 +136,10 @@ export function buildProviderModelAuthSourcePlan(params: {
       } else if (params.allowCooldown) {
         profiles = { kind: "usable", explicitOrder, profiles: available.slice(0, 1) };
       } else {
-        profiles = { kind: "all-cooldown", explicitOrder, first: available[0] };
+        const [firstAvailable] = available;
+        profiles = firstAvailable
+          ? { kind: "all-cooldown", explicitOrder, first: firstAvailable }
+          : { kind: "empty", explicitOrder };
       }
     }
   }
diff --git a/src/auto-reply/chunk.ts b/src/auto-reply/chunk.ts
index ff6536ed37cb..a906a5715377 100644
--- a/src/auto-reply/chunk.ts
+++ b/src/auto-reply/chunk.ts
@@ -477,7 +477,7 @@ export function chunkMarkdownText(text: string, limit: number): string[] {
     }
 
     let rawChunk = `${reopenPrefix}${rawContent}`;
-    const brokeOnSeparator = breakIdx < text.length && /\s/.test(text[breakIdx]);
+    const brokeOnSeparator = breakIdx < text.length && /\s/.test(text.charAt(breakIdx));
     let nextStart = Math.min(text.length, breakIdx + (brokeOnSeparator ? 1 : 0));
 
     if (fenceToSplit) {
@@ -536,7 +536,7 @@ function scanParenAwareBreakpoints(
     if (!isAllowed(i)) {
       continue;
     }
-    const char = text[i];
+    const char = text.charAt(i);
     if (char === "(") {
       depth += 1;
       continue;
diff --git a/src/auto-reply/command-auth.ts b/src/auto-reply/command-auth.ts
index d544c384d36a..04a5d0b24499 100644
--- a/src/auto-reply/command-auth.ts
+++ b/src/auto-reply/command-auth.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Command authorization helpers for owner and allowlist checks. */
 import {
   normalizeOptionalLowercaseString,
@@ -97,8 +98,8 @@ function resolveProviderFromContext(
   const inferred = inferredProviders.candidates;
   if (inferred.length === 1) {
     return {
-      providerId: inferred[0].providerId,
-      hadResolutionError: inferred[0].hadResolutionError,
+      providerId: expectDefined(inferred[0], "inferred entry at 0").providerId,
+      hadResolutionError: expectDefined(inferred[0], "inferred entry at 0").hadResolutionError,
     };
   }
   return {
diff --git a/src/auto-reply/commands-registry-normalize.ts b/src/auto-reply/commands-registry-normalize.ts
index 4e8218d3d048..f9427c73ada8 100644
--- a/src/auto-reply/commands-registry-normalize.ts
+++ b/src/auto-reply/commands-registry-normalize.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Normalizes slash-command text aliases and builds command detection caches. */
 import {
   normalizeLowercaseStringOrEmpty,
@@ -80,7 +81,7 @@ export function normalizeCommandBody(raw: string, options?: CommandNormalizeOpti
   const normalized = colonMatch
     ? (() => {
         const [, command, rest] = colonMatch;
-        const normalizedRest = rest.trimStart();
+        const normalizedRest = expectDefined(rest, "commands registry normalize rest").trimStart();
         return normalizedRest ? `/${command} ${normalizedRest}` : `/${command}`;
       })()
     : singleLine;
diff --git a/src/auto-reply/commands-registry.ts b/src/auto-reply/commands-registry.ts
index dcc2e53ef7ec..350753ba44d4 100644
--- a/src/auto-reply/commands-registry.ts
+++ b/src/auto-reply/commands-registry.ts
@@ -1,4 +1,5 @@
 /** Command-registry facade for native specs, text aliases, argument parsing, and menus. */
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
 import { DEFAULT_MODEL, DEFAULT_PROVIDER } from "../agents/defaults.js";
 import {
@@ -205,7 +206,7 @@ function parsePositionalArgs(definitions: CommandArgDefinition[], raw: string):
       values[definition.name] = tokens.slice(index).join(" ");
       break;
     }
-    values[definition.name] = tokens[index];
+    values[definition.name] = expectDefined(tokens[index], "command argument token");
     index += 1;
   }
   return values;
diff --git a/src/auto-reply/heartbeat-filter.ts b/src/auto-reply/heartbeat-filter.ts
index 7b15199be88d..b6aba1b5558f 100644
--- a/src/auto-reply/heartbeat-filter.ts
+++ b/src/auto-reply/heartbeat-filter.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Transcript filter for removing heartbeat-only prompt/ack artifacts.
 import { isRecord } from "@openclaw/normalization-core/record-coerce";
 import { normalizeOptionalString as readString } from "@openclaw/normalization-core/string-coerce";
@@ -348,7 +349,11 @@ function advancePastAdjacentToolResults(
   startIndex: number,
 ): number {
   let index = startIndex;
-  while (index < messages.length && isToolResultMessage(messages[index])) {
+  while (index < messages.length) {
+    const message = messages.at(index);
+    if (!message || !isToolResultMessage(message)) {
+      break;
+    }
     index++;
   }
   return index;
@@ -362,17 +367,19 @@ function hasCompletedVisibleHeartbeatResponseToolCall(
   messages: HeartbeatTranscriptMessage[],
   index: number,
 ): boolean {
-  const visibleCalls = collectVisibleHeartbeatResponseToolCalls(messages[index]);
+  const message = messages.at(index);
+  if (!message) {
+    return false;
+  }
+  const visibleCalls = collectVisibleHeartbeatResponseToolCalls(message);
   if (visibleCalls.length === 0) {
     return false;
   }
   const callIds = new Set(visibleCalls.flatMap((call) => collectToolCallIds(call)));
-  for (
-    let resultIndex = index + 1;
-    resultIndex < messages.length && isToolResultCompletionCandidate(messages[resultIndex]);
-    resultIndex++
-  ) {
-    const result = messages[resultIndex];
+  for (const result of messages.slice(index + 1)) {
+    if (!isToolResultCompletionCandidate(result)) {
+      break;
+    }
     if (!hasSuccessfulToolResultMessage(result)) {
       continue;
     }
@@ -399,7 +406,10 @@ function resolveHeartbeatArtifactSpanEnd(
   let sawNonTerminalAssistantOutput = false;
 
   while (index < messages.length) {
-    const message = messages[index];
+    const message = messages.at(index);
+    if (!message) {
+      break;
+    }
     if (isRealNonHeartbeatUserMessage(message, heartbeatPrompt)) {
       break;
     }
@@ -458,15 +468,17 @@ export function filterHeartbeatTranscriptArtifacts<T extends { role: string; con
   const result: T[] = [];
   let i = 0;
   while (i < messages.length) {
-    if (!isHeartbeatUserMessage(messages[i], heartbeatPrompt)) {
-      result.push(messages[i]);
+    if (
+      !isHeartbeatUserMessage(expectDefined(messages[i], "messages entry at i"), heartbeatPrompt)
+    ) {
+      result.push(expectDefined(messages[i], "messages entry at i"));
       i++;
       continue;
     }
 
     const next = resolveHeartbeatArtifactSpanEnd(messages, i, ackMaxChars, heartbeatPrompt);
     if (next === undefined) {
-      result.push(messages[i]);
+      result.push(expectDefined(messages[i], "messages entry at i"));
       i++;
       continue;
     }
diff --git a/src/auto-reply/heartbeat.ts b/src/auto-reply/heartbeat.ts
index 6cf28fd5afd3..ac4c9814bf82 100644
--- a/src/auto-reply/heartbeat.ts
+++ b/src/auto-reply/heartbeat.ts
@@ -265,8 +265,7 @@ export function parseHeartbeatTasks(content: string): HeartbeatTask[] {
   const lines = stripHeartbeatHtmlComments(content);
   let inTasksBlock = false;
 
-  for (let i = 0; i < lines.length; i++) {
-    const line = lines[i];
+  for (const [i, line] of lines.entries()) {
     const trimmed = line.trim();
 
     // Detect tasks block start.
@@ -305,8 +304,7 @@ export function parseHeartbeatTasks(content: string): HeartbeatTask[] {
       let prompt = "";
 
       // Look ahead for interval and prompt
-      for (let j = i + 1; j < lines.length; j++) {
-        const nextLine = lines[j];
+      for (const nextLine of lines.slice(i + 1)) {
         const nextTrimmed = nextLine.trim();
 
         // End of this task
diff --git a/src/auto-reply/reply/acp-stream-settings.ts b/src/auto-reply/reply/acp-stream-settings.ts
index 77bbb13807ea..6aed564daf0e 100644
--- a/src/auto-reply/reply/acp-stream-settings.ts
+++ b/src/auto-reply/reply/acp-stream-settings.ts
@@ -25,6 +25,10 @@ const ACP_TAG_VISIBILITY_DEFAULTS: Record<AcpSessionUpdateTag, boolean> = {
   agent_thought_chunk: false,
 };
 
+function isAcpSessionUpdateTag(tag: string): tag is AcpSessionUpdateTag {
+  return Object.hasOwn(ACP_TAG_VISIBILITY_DEFAULTS, tag);
+}
+
 /** ACP delivery strategy for projected assistant output. */
 type AcpDeliveryMode = "live" | "final_only";
 export type AcpHiddenBoundarySeparator = "none" | "space" | "newline" | "paragraph";
@@ -148,12 +152,16 @@ export function isAcpTagVisible(settings: AcpProjectionSettings, tag: string | u
   if (!tag) {
     return true;
   }
-  const override = settings.tagVisibility[tag as AcpSessionUpdateTag];
+  if (!isAcpSessionUpdateTag(tag)) {
+    return true;
+  }
+  const override = settings.tagVisibility[tag];
   if (typeof override === "boolean") {
     return override;
   }
-  if (Object.hasOwn(ACP_TAG_VISIBILITY_DEFAULTS, tag)) {
-    return ACP_TAG_VISIBILITY_DEFAULTS[tag as AcpSessionUpdateTag];
+  const defaultVisibility = ACP_TAG_VISIBILITY_DEFAULTS[tag];
+  if (defaultVisibility === undefined) {
+    throw new Error(`Missing ACP visibility default for ${tag}`);
   }
-  return true;
+  return defaultVisibility;
 }
diff --git a/src/auto-reply/reply/agent-runner-execution.ts b/src/auto-reply/reply/agent-runner-execution.ts
index 7bbe3e11fded..f3b3dadcc14e 100644
--- a/src/auto-reply/reply/agent-runner-execution.ts
+++ b/src/auto-reply/reply/agent-runner-execution.ts
@@ -1,5 +1,6 @@
 /** Agent-runner execution loop, fallback handling, and user-facing failure mapping. */
 import crypto from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   hasNonEmptyString,
   normalizeLowercaseStringOrEmpty,
@@ -564,7 +565,7 @@ function collapseRepeatedFailureDetail(message: string): string {
     .map((part) => part.trim())
     .filter(Boolean);
   if (parts.length >= 2 && parts.every((part) => part === parts[0])) {
-    return parts[0];
+    return expectDefined(parts[0], "parts entry at 0");
   }
   return message.trim();
 }
diff --git a/src/auto-reply/reply/agent-runner-usage-line.ts b/src/auto-reply/reply/agent-runner-usage-line.ts
index 8af1d1021a19..1594cbe9c72b 100644
--- a/src/auto-reply/reply/agent-runner-usage-line.ts
+++ b/src/auto-reply/reply/agent-runner-usage-line.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 import { hasNonzeroUsage, type NormalizedUsage } from "../../agents/usage.js";
 import type { OpenClawConfig } from "../../config/config.js";
 import type { PluginHookReplyUsageState } from "../../plugins/hook-types.js";
@@ -121,7 +122,7 @@ export const appendUsageLine = (payloads: ReplyPayload[], line: string): ReplyPa
   if (index === -1) {
     return [...payloads, { text: line }];
   }
-  const existing = payloads[index];
+  const existing = expectDefined(payloads[index], "payloads entry at index");
   const existingText = existing.text ?? "";
   const separator = existingText.endsWith("\n") ? "" : "\n";
   const next = {
diff --git a/src/auto-reply/reply/agent-runner.ts b/src/auto-reply/reply/agent-runner.ts
index 1126ffb3e7c9..f9e7d6af4d5f 100644
--- a/src/auto-reply/reply/agent-runner.ts
+++ b/src/auto-reply/reply/agent-runner.ts
@@ -1,5 +1,6 @@
 // Orchestrates reply agent execution, payload building, and delivery callbacks.
 import crypto from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import {
   hasSessionAutoModelFallbackProvenance,
@@ -643,7 +644,10 @@ function derivePromptSegments(prompt: string | undefined): TracePromptSegmentVie
           end += 1;
         }
         if (end < lines.length) {
-          addChars(tagMatch[1], lines.slice(index, end + 1).join("\n").length);
+          addChars(
+            expectDefined(tagMatch[1], "tag match capture group 1"),
+            lines.slice(index, end + 1).join("\n").length,
+          );
           index = end + 1;
           while ((lines[index] ?? "") === "") {
             index += 1;
diff --git a/src/auto-reply/reply/commands-allowlist.ts b/src/auto-reply/reply/commands-allowlist.ts
index e0406a180b58..fb360b681ecc 100644
--- a/src/auto-reply/reply/commands-allowlist.ts
+++ b/src/auto-reply/reply/commands-allowlist.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Handles /allowlist commands across config and pairing-store targets. */
 import {
   normalizeOptionalLowercaseString,
@@ -109,7 +110,7 @@ function parseAllowlistCommand(raw: string): AllowlistCommand | null {
   }
 
   for (; i < tokens.length; i += 1) {
-    const token = tokens[i];
+    const token = expectDefined(tokens[i], "tokens entry at i");
     const lowered = normalizeOptionalLowercaseString(token) ?? "";
     if (lowered === "--resolve" || lowered === "resolve") {
       resolve = true;
diff --git a/src/auto-reply/reply/commands-approve.ts b/src/auto-reply/reply/commands-approve.ts
index f3dd6831d1f3..32d06bcfa652 100644
--- a/src/auto-reply/reply/commands-approve.ts
+++ b/src/auto-reply/reply/commands-approve.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Implements approval commands for pending tool and execution requests.
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import {
@@ -68,7 +69,7 @@ function parseApproveCommand(raw: string): ParsedApproveCommand | null {
     return {
       ok: true,
       decision: DECISION_ALIASES[second],
-      id: tokens[0],
+      id: expectDefined(tokens[0], "tokens entry at 0"),
     };
   }
   return { ok: false, error: APPROVE_USAGE_TEXT };
diff --git a/src/auto-reply/reply/commands-export-session.ts b/src/auto-reply/reply/commands-export-session.ts
index aeb5a87f84c0..a05d8bbdc391 100644
--- a/src/auto-reply/reply/commands-export-session.ts
+++ b/src/auto-reply/reply/commands-export-session.ts
@@ -2,6 +2,7 @@
 import fsp from "node:fs/promises";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isRecord } from "@openclaw/normalization-core/record-coerce";
 import { readAcpSessionMetaForEntry } from "../../acp/runtime/session-meta.js";
 import {
@@ -191,7 +192,15 @@ async function generateHtml(sessionData: SessionData): Promise<string> {
     ["MARKED_JS", markedJs],
     ["HIGHLIGHT_JS", hljsJs],
     ["JS", templateJs],
-  ].reduce((html, [name, value]) => replaceHtmlPlaceholder(html, name, value), template);
+  ].reduce(
+    (html, [name, value]) =>
+      replaceHtmlPlaceholder(
+        html,
+        expectDefined(name, "commands export session name"),
+        expectDefined(value, "commands export session value"),
+      ),
+    template,
+  );
 }
 
 function addCollisionSuffix(filePath: string, suffix: number): string {
diff --git a/src/auto-reply/reply/config-mutations.ts b/src/auto-reply/reply/config-mutations.ts
index e2747a7b78f8..c410675f38ac 100644
--- a/src/auto-reply/reply/config-mutations.ts
+++ b/src/auto-reply/reply/config-mutations.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Config mutation helpers used by chat commands that edit OpenClaw config. */
 import { setConfigValueAtPath, unsetConfigValueAtPath } from "../../config/config-paths.js";
 import {
@@ -22,7 +23,7 @@ function assertValidConfig(
 ): { config: OpenClawConfig } {
   const validated = validateConfigObjectWithPlugins(next);
   if (!validated.ok) {
-    const issue = validated.issues[0];
+    const issue = expectDefined(validated.issues[0], "issues entry at 0");
     throw new AutoReplyConfigMutationError(
       `Config invalid after ${action} (${issue.path}: ${issue.message}).`,
     );
diff --git a/src/auto-reply/reply/context-treemap.ts b/src/auto-reply/reply/context-treemap.ts
index a60dc0f628e4..b45c4b49309a 100644
--- a/src/auto-reply/reply/context-treemap.ts
+++ b/src/auto-reply/reply/context-treemap.ts
@@ -3,6 +3,7 @@ import crypto from "node:crypto";
 import { writeFile } from "node:fs/promises";
 import path from "node:path";
 import zlib from "node:zlib";
+import { expectDefined } from "@openclaw/normalization-core";
 import type { SessionSystemPromptReport } from "../../config/sessions/types.js";
 import { resolvePreferredOpenClawTmpDir } from "../../infra/tmp-openclaw-dir.js";
 import { estimateTokensFromChars } from "../../utils/cjk-chars.js";
@@ -150,13 +151,13 @@ function layoutBinary<T extends { value: number }>(rawItems: T[], rect: Rect): P
     return [];
   }
   if (items.length === 1) {
-    return [{ item: items[0], rect }];
+    return [{ item: expectDefined(items[0], "items entry at 0"), rect }];
   }
   const total = totalValue(items);
   let splitIndex = 1;
   let splitSum = items[0]?.value ?? 0;
   for (let i = 1; i < items.length - 1; i += 1) {
-    const next = splitSum + items[i].value;
+    const next = splitSum + expectDefined(items[i], "items entry at i").value;
     if (Math.abs(total / 2 - next) > Math.abs(total / 2 - splitSum)) {
       break;
     }
@@ -234,9 +235,9 @@ class PngCanvas {
     const cursorY = Math.floor(y);
     for (const rawChar of text) {
       const char = rawChar.toUpperCase();
-      const glyph = FONT[char] ?? FONT[" "];
+      const glyph = expectDefined(FONT[char] ?? FONT[" "], "treemap font glyph");
       for (let row = 0; row < glyph.length; row += 1) {
-        const line = glyph[row];
+        const line = expectDefined(glyph[row], "treemap glyph row");
         for (let col = 0; col < line.length; col += 1) {
           if (line[col] !== "1") {
             continue;
diff --git a/src/auto-reply/reply/directive-parsing.ts b/src/auto-reply/reply/directive-parsing.ts
index 67a7c9f51fd0..58be6e276024 100644
--- a/src/auto-reply/reply/directive-parsing.ts
+++ b/src/auto-reply/reply/directive-parsing.ts
@@ -2,12 +2,12 @@
 export function skipDirectiveArgPrefix(raw: string): number {
   let i = 0;
   const len = raw.length;
-  while (i < len && /\s/.test(raw[i])) {
+  while (i < len && /\s/.test(raw.charAt(i))) {
     i += 1;
   }
   if (raw[i] === ":") {
     i += 1;
-    while (i < len && /\s/.test(raw[i])) {
+    while (i < len && /\s/.test(raw.charAt(i))) {
       i += 1;
     }
   }
@@ -21,21 +21,21 @@ export function takeDirectiveToken(
 ): { token: string | null; nextIndex: number } {
   let i = startIndex;
   const len = raw.length;
-  while (i < len && /\s/.test(raw[i])) {
+  while (i < len && /\s/.test(raw.charAt(i))) {
     i += 1;
   }
   if (i >= len) {
     return { token: null, nextIndex: i };
   }
   const start = i;
-  while (i < len && !/\s/.test(raw[i])) {
+  while (i < len && !/\s/.test(raw.charAt(i))) {
     i += 1;
   }
   if (start === i) {
     return { token: null, nextIndex: i };
   }
   const token = raw.slice(start, i);
-  while (i < len && /\s/.test(raw[i])) {
+  while (i < len && /\s/.test(raw.charAt(i))) {
     i += 1;
   }
   return { token, nextIndex: i };
diff --git a/src/auto-reply/reply/directives.ts b/src/auto-reply/reply/directives.ts
index a768adf80bfd..83bdd26c4b9e 100644
--- a/src/auto-reply/reply/directives.ts
+++ b/src/auto-reply/reply/directives.ts
@@ -46,17 +46,17 @@ const matchLevelDirective = (
   const start = match.index;
   const directiveEnd = match.index + match[0].length;
   let i = directiveEnd;
-  while (i < body.length && /\s/.test(body[i])) {
+  while (i < body.length && /\s/.test(body.charAt(i))) {
     i += 1;
   }
   if (body[i] === ":") {
     i += 1;
-    while (i < body.length && /\s/.test(body[i])) {
+    while (i < body.length && /\s/.test(body.charAt(i))) {
       i += 1;
     }
   }
   const argStart = i;
-  while (i < body.length && /[A-Za-z-]/.test(body[i])) {
+  while (i < body.length && /[A-Za-z-]/.test(body.charAt(i))) {
     i += 1;
   }
   const candidate = i > argStart ? body.slice(argStart, i) : undefined;
diff --git a/src/auto-reply/reply/history-media.ts b/src/auto-reply/reply/history-media.ts
index 1a88cdb554d5..e31aba1665fa 100644
--- a/src/auto-reply/reply/history-media.ts
+++ b/src/auto-reply/reply/history-media.ts
@@ -1,5 +1,6 @@
 // Extracts media attachment references from reply history entries.
 import { mimeTypeFromFilePath } from "@openclaw/media-core/mime";
+import { expectDefined } from "@openclaw/normalization-core";
 import { asFiniteNumber } from "@openclaw/normalization-core/number-coercion";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import type { MsgContext } from "../templating.js";
@@ -67,7 +68,7 @@ export function resolveRecentInboundHistoryImages(params: {
   const seen = new Set<string>();
   const entries = resolveHistoryEntries(params.ctx);
   for (let index = entries.length - 1; index >= 0 && out.length < limit; index -= 1) {
-    const entry = entries[index];
+    const entry = expectDefined(entries[index], "entries entry at index");
     const timestamp = resolveTimestamp(entry?.timestamp);
     if (timestamp === undefined || Math.abs(nowMs - timestamp) > ttlMs) {
       continue;
diff --git a/src/auto-reply/reply/model-selection-directive.ts b/src/auto-reply/reply/model-selection-directive.ts
index 78d00acd1704..6bcd89d39159 100644
--- a/src/auto-reply/reply/model-selection-directive.ts
+++ b/src/auto-reply/reply/model-selection-directive.ts
@@ -1,5 +1,6 @@
 // Normalizes model selection directives into provider and model ids.
 import { normalizeProviderId } from "@openclaw/model-catalog-core/provider-id";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { modelKey } from "../../agents/model-ref-shared.js";
 import {
@@ -85,14 +86,19 @@ function boundedLevenshteinDistance(a: string, b: string, maxDistance: number):
 
   for (let i = 1; i <= aLen; i++) {
     curr[0] = i;
-    let rowMin = curr[0];
+    let rowMin = expectDefined(curr[0], "curr entry at 0");
 
     const aChar = a.charCodeAt(i - 1);
     for (let j = 1; j <= bLen; j++) {
       const cost = aChar === b.charCodeAt(j - 1) ? 0 : 1;
-      curr[j] = Math.min(prev[j] + 1, curr[j - 1] + 1, prev[j - 1] + cost);
-      if (curr[j] < rowMin) {
-        rowMin = curr[j];
+      const distance = Math.min(
+        expectDefined(prev[j], "prev entry at j") + 1,
+        expectDefined(curr[j - 1], "curr entry at j 1") + 1,
+        expectDefined(prev[j - 1], "prev entry at j 1") + cost,
+      );
+      curr[j] = distance;
+      if (distance < rowMin) {
+        rowMin = distance;
       }
     }
 
@@ -101,11 +107,11 @@ function boundedLevenshteinDistance(a: string, b: string, maxDistance: number):
     }
 
     for (let j = 0; j <= bLen; j++) {
-      prev[j] = curr[j];
+      prev[j] = expectDefined(curr[j], "model selection directive edit-distance row");
     }
   }
 
-  const dist = prev[bLen];
+  const dist = expectDefined(prev[bLen], "prev entry at b len");
   if (dist > maxDistance) {
     return null;
   }
diff --git a/src/auto-reply/reply/post-compaction-context.ts b/src/auto-reply/reply/post-compaction-context.ts
index d0e92d26c4bc..e287df68a074 100644
--- a/src/auto-reply/reply/post-compaction-context.ts
+++ b/src/auto-reply/reply/post-compaction-context.ts
@@ -1,6 +1,7 @@
 // Loads post-compaction context summaries for continuation prompts.
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { resolveAgentContextLimits } from "../../agents/agent-scope.js";
@@ -187,7 +188,7 @@ export function extractSections(
       const headingMatch = line.match(/^(#{2,3})\s+(.+?)\s*$/);
 
       if (headingMatch) {
-        const level = headingMatch[1].length; // 2 or 3
+        const level = expectDefined(headingMatch[1], "heading match capture group 1").length; // 2 or 3
         const headingText = headingMatch[2];
 
         if (!inSection) {
diff --git a/src/auto-reply/reply/queue/drain.ts b/src/auto-reply/reply/queue/drain.ts
index 954652fbadec..2019f9973d9a 100644
--- a/src/auto-reply/reply/queue/drain.ts
+++ b/src/auto-reply/reply/queue/drain.ts
@@ -1,4 +1,5 @@
 import { createHash } from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { runAgentHarnessBeforeMessageWriteHook } from "../../../agents/harness/hook-helpers.js";
 import { normalizeChatType } from "../../../channels/chat-type.js";
@@ -624,7 +625,10 @@ function consumeQueueSummaryDelivery(
         (entry) => entry.sources.includes(source) || entry.sourceRefs.has(source),
       );
       if (elisionIndex >= 0) {
-        const entry = queue.summaryElisions[elisionIndex];
+        const entry = expectDefined(
+          queue.summaryElisions[elisionIndex],
+          "summary elisions entry at elision index",
+        );
         const elidedSourceIndex = entry.sources.indexOf(entry.sourceRefs.get(source) ?? source);
         entry.sources.splice(elidedSourceIndex, 1);
         entry.count = entry.sources.length;
@@ -659,7 +663,7 @@ function releaseQueueSummaryDeliveryForRetry(
 function dropAbortedQueueSummarySources(queue: FollowupQueueSummaryState): number {
   let dropped = 0;
   for (let index = queue.summarySources.length - 1; index >= 0; index -= 1) {
-    const source = queue.summarySources[index];
+    const source = expectDefined(queue.summarySources[index], "summary sources entry at index");
     if (!isFollowupRunAborted(source)) {
       continue;
     }
@@ -775,7 +779,7 @@ async function dropAbortedFollowups(
 ): Promise<number> {
   let dropped = 0;
   for (let index = items.length - 1; index >= 0; index -= 1) {
-    const item = items[index];
+    const item = expectDefined(items[index], "items entry at index");
     if (isFollowupRunAborted(item)) {
       await runFollowup(item);
       completeFollowupRunLifecycle(item);
@@ -979,7 +983,7 @@ async function drainElidedOverflowSummary(params: {
         )
       : [];
   for (let index = entry.sources.length - 1; index >= 0; index -= 1) {
-    const source = entry.sources[index];
+    const source = expectDefined(entry.sources[index], "sources entry at index");
     if (!isFollowupRunAborted(source)) {
       continue;
     }
diff --git a/src/auto-reply/reply/queue/state.ts b/src/auto-reply/reply/queue/state.ts
index c1d513c26aad..501d4840a0a5 100644
--- a/src/auto-reply/reply/queue/state.ts
+++ b/src/auto-reply/reply/queue/state.ts
@@ -77,8 +77,7 @@ export function trimSummaryElisionsToCap(queue: SummaryElisionCapState): void {
   );
   while (sourceCount > queue.cap) {
     let evicted = false;
-    for (let entryIndex = 0; entryIndex < queue.summaryElisions.length; entryIndex += 1) {
-      const entry = queue.summaryElisions[entryIndex];
+    for (const [entryIndex, entry] of queue.summaryElisions.entries()) {
       const sourceIndex = entry.sources.findIndex(
         (source) => !queue.activeSummarySources.has(source),
       );
diff --git a/src/auto-reply/reply/reply-payloads-dedupe.ts b/src/auto-reply/reply/reply-payloads-dedupe.ts
index 1822f0f96bd1..1460dec49c5b 100644
--- a/src/auto-reply/reply/reply-payloads-dedupe.ts
+++ b/src/auto-reply/reply/reply-payloads-dedupe.ts
@@ -56,8 +56,7 @@ export function filterMessagingToolMediaDuplicates(params: {
   }
 
   let nextPayloads: ReplyPayload[] | undefined;
-  for (let index = 0; index < payloads.length; index++) {
-    const payload = payloads[index];
+  for (const [index, payload] of payloads.entries()) {
     const mediaUrl = payload.mediaUrl;
     const mediaUrls = payload.mediaUrls;
     const stripSingle = mediaUrl && sentSet.has(normalizeMediaForDedupe(mediaUrl));
@@ -65,8 +64,7 @@ export function filterMessagingToolMediaDuplicates(params: {
     let filteredUrls: string[] | undefined;
     let strippedMediaUrls = false;
     if (mediaUrls?.length) {
-      for (let mediaIndex = 0; mediaIndex < mediaUrls.length; mediaIndex++) {
-        const url = mediaUrls[mediaIndex];
+      for (const [mediaIndex, url] of mediaUrls.entries()) {
         if (sentSet.has(normalizeMediaForDedupe(url))) {
           strippedMediaUrls = true;
           if (!filteredUrls) {
diff --git a/src/auto-reply/reply/streaming-directives.ts b/src/auto-reply/reply/streaming-directives.ts
index e118bcd6a221..41fd9e6570e5 100644
--- a/src/auto-reply/reply/streaming-directives.ts
+++ b/src/auto-reply/reply/streaming-directives.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Converts streaming reply directives into payload delivery decisions.
 import { hasOutboundReplyContent } from "openclaw/plugin-sdk/reply-payload";
 import { parseInlineDirectives } from "../../utils/directive-tags.js";
@@ -75,7 +76,8 @@ export const splitTrailingDirective = (
 
   const prefixMatch = text.match(/(?:^|\n)(MEDIA|MEDI|MED|ME|M)$/i);
   if (prefixMatch) {
-    const prefixStart = text.length - prefixMatch[1].length;
+    const prefixStart =
+      text.length - expectDefined(prefixMatch[1], "prefix match capture group 1").length;
     if (prefixStart < bufferStart) {
       bufferStart = prefixStart;
     }
diff --git a/src/auto-reply/reply/strip-inbound-meta.ts b/src/auto-reply/reply/strip-inbound-meta.ts
index 1b69742a88a3..c6e35b594630 100644
--- a/src/auto-reply/reply/strip-inbound-meta.ts
+++ b/src/auto-reply/reply/strip-inbound-meta.ts
@@ -179,8 +179,12 @@ function stripActiveMemoryPromptPrefixBlocks(lines: string[]): string[] {
   const result: string[] = [];
 
   for (let index = 0; index < lines.length; index += 1) {
+    const line = lines.at(index);
+    if (line === undefined) {
+      break;
+    }
     if (
-      lines[index]?.trim() === UNTRUSTED_CONTEXT_HEADER &&
+      line.trim() === UNTRUSTED_CONTEXT_HEADER &&
       lines[index + 1]?.trim() === ACTIVE_MEMORY_OPEN_TAG
     ) {
       let closeIndex = -1;
@@ -199,7 +203,7 @@ function stripActiveMemoryPromptPrefixBlocks(lines: string[]): string[] {
       }
     }
 
-    result.push(lines[index]);
+    result.push(line);
   }
 
   return result;
@@ -238,8 +242,10 @@ export function stripInboundMetadata(text: string): string {
   let inFencedJson = false;
 
   for (let i = 0; i < strippedLeadingPrefixLines.length; i++) {
-    const line = strippedLeadingPrefixLines[i];
-
+    const line = strippedLeadingPrefixLines.at(i);
+    if (line === undefined) {
+      break;
+    }
     // Channel untrusted context is appended by OpenClaw as a terminal metadata suffix.
     // When this structured header appears, drop it and everything that follows.
     if (!inMetaBlock && shouldStripTrailingUntrustedContext(strippedLeadingPrefixLines, i)) {
@@ -310,25 +316,34 @@ export function stripLeadingInboundMetadata(text: string): string {
   const lines = stripActiveMemoryPromptPrefixBlocks(text.split("\n"));
   let index = 0;
 
-  while (index < lines.length && lines[index] === "") {
+  while (lines.at(index) === "") {
     index++;
   }
-  if (index >= lines.length) {
+  const firstLine = lines.at(index);
+  if (firstLine === undefined) {
     return "";
   }
 
-  const strippedDeliveryHint = isMessageToolDeliveryHintLine(lines[index]);
-  while (index < lines.length && isMessageToolDeliveryHintLine(lines[index])) {
+  const strippedDeliveryHint = isMessageToolDeliveryHintLine(firstLine);
+  while (true) {
+    const line = lines.at(index);
+    if (line === undefined || !isMessageToolDeliveryHintLine(line)) {
+      break;
+    }
     index++;
-    while (index < lines.length && lines[index] === "") {
+    while (lines.at(index) === "") {
       index++;
     }
   }
-  if (index >= lines.length) {
+  const firstContentLine = lines.at(index);
+  if (firstContentLine === undefined) {
     return "";
   }
 
-  if (!isInboundMetaSentinelLine(lines[index]) && !isChatWindowContextHeaderLine(lines[index])) {
+  if (
+    !isInboundMetaSentinelLine(firstContentLine) &&
+    !isChatWindowContextHeaderLine(firstContentLine)
+  ) {
     const strippedNoLeading = stripTrailingUntrustedContextSuffix(
       strippedDeliveryHint ? lines.slice(index) : lines,
     );
@@ -336,7 +351,10 @@ export function stripLeadingInboundMetadata(text: string): string {
   }
 
   while (index < lines.length) {
-    const line = lines[index];
+    const line = lines.at(index);
+    if (line === undefined) {
+      break;
+    }
     if (isChatWindowContextHeaderLine(line)) {
       index = skipChatWindowContextBlock(lines, index);
       continue;
@@ -351,19 +369,19 @@ export function stripLeadingInboundMetadata(text: string): string {
     }
 
     index++;
-    if (index < lines.length && lines[index].trim() === "```json") {
+    if (lines.at(index)?.trim() === "```json") {
       index++;
-      while (index < lines.length && lines[index].trim() !== "```") {
+      while (index < lines.length && lines.at(index)?.trim() !== "```") {
         index++;
       }
-      if (index < lines.length && lines[index].trim() === "```") {
+      if (lines.at(index)?.trim() === "```") {
         index++;
       }
     } else {
       return text;
     }
 
-    while (index < lines.length && lines[index].trim() === "") {
+    while (lines.at(index)?.trim() === "") {
       index++;
     }
   }
diff --git a/src/auto-reply/test-helpers/command-auth-registry-fixture.ts b/src/auto-reply/test-helpers/command-auth-registry-fixture.ts
index 9f9d9819f31c..379a99589207 100644
--- a/src/auto-reply/test-helpers/command-auth-registry-fixture.ts
+++ b/src/auto-reply/test-helpers/command-auth-registry-fixture.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Test registry fixture for command authorization across Discord and phone-based channels. */
 import { lowercasePreservingWhitespace } from "@openclaw/normalization-core/string-coerce";
 import { normalizeStringEntries } from "@openclaw/normalization-core/string-normalization";
@@ -24,12 +25,16 @@ function normalizePhoneAllowFromEntries(allowFrom: Array<string | number>): stri
       }
       if (/^(\d+)(?::\d+)?@s\.whatsapp\.net$/i.test(stripped)) {
         const match = stripped.match(/^(\d+)(?::\d+)?@s\.whatsapp\.net$/i);
-        return match ? normalizeE164(match[1]) : null;
+        return match
+          ? normalizeE164(expectDefined(match[1], "command auth registry fixture regex capture 1"))
+          : null;
       }
       // WhatsApp LID values are numeric identifiers; test fixtures map them like phone ids.
       if (/^(\d+)@lid$/i.test(stripped)) {
         const match = stripped.match(/^(\d+)@lid$/i);
-        return match ? normalizeE164(match[1]) : null;
+        return match
+          ? normalizeE164(expectDefined(match[1], "command auth registry fixture regex capture 1"))
+          : null;
       }
       if (stripped.includes("@")) {
         return null;
diff --git a/src/auto-reply/usage-bar/translator.ts b/src/auto-reply/usage-bar/translator.ts
index 3846d75c96bf..6586b163ec63 100644
--- a/src/auto-reply/usage-bar/translator.ts
+++ b/src/auto-reply/usage-bar/translator.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 export type UsageBarTemplate = Record<string, unknown>;
 export type UsageContract = Record<string, unknown>;
 type Vocab = Record<string, unknown>;
@@ -92,8 +93,8 @@ function meter(value: unknown, width: number, scale: unknown): string {
   if (glyphs.length < 2 || width < 1) {
     return "";
   }
-  const empty = glyphs[0];
-  const full = glyphs[glyphs.length - 1];
+  const empty = expectDefined(glyphs[0], "glyphs entry at 0");
+  const full = expectDefined(glyphs[glyphs.length - 1], "glyphs entry at glyphs.length 1");
   const total = norm(value) * width;
   const fullc = Math.trunc(total);
   const cells: string[] = [];
@@ -101,7 +102,12 @@ function meter(value: unknown, width: number, scale: unknown): string {
     cells.push(full);
   }
   if (cells.length < width) {
-    cells.push(glyphs[Math.round((total - fullc) * (glyphs.length - 1))]);
+    cells.push(
+      expectDefined(
+        glyphs[Math.round((total - fullc) * (glyphs.length - 1))],
+        "glyphs entry at math.round((total fullc) * (glyphs.length 1))",
+      ),
+    );
   }
   while (cells.length < width) {
     cells.push(empty);
@@ -138,7 +144,7 @@ function applyVerb(name: string, args: string[], value: unknown, vocab: Vocab):
     }
     case "meter": {
       const width = args[0] ? Number.parseInt(args[0], 10) || 5 : 5;
-      const scale = args.length > 1 ? vocab[args[1]] : undefined;
+      const scale = args.length > 1 ? vocab[expectDefined(args[1], "args entry at 1")] : undefined;
       return meter(value, width, scale);
     }
     default:
@@ -170,7 +176,7 @@ function interp(text: string, ctx: unknown, vocab: Vocab): string {
     let fallback: string | undefined;
     for (const segRaw of parts.slice(1)) {
       const seg = segRaw.trim();
-      const name = seg.split(":")[0];
+      const name = expectDefined(seg.split(":")[0], 'seg.split(":") entry at 0');
       if (VERB_NAMES.has(name)) {
         ops.push({ name, args: seg.split(":").slice(1) });
       } else {
@@ -212,7 +218,15 @@ function renderSegment(seg: Segment, ctx: unknown, vocab: Vocab): string | null
     items.forEach((el, i) => {
       let iv = vocab;
       if (names && names.length > 0) {
-        iv = { ...vocab, "*": vocab[names[Math.min(i, names.length - 1)]] };
+        iv = {
+          ...vocab,
+          "*": vocab[
+            expectDefined(
+              names[Math.min(i, names.length - 1)],
+              "names entry at math.min(i, names.length 1)",
+            )
+          ],
+        };
       }
       const r = interp(itemTpl, el, iv);
       if (r) {
diff --git a/src/channels/chat-meta.ts b/src/channels/chat-meta.ts
index ece54c22b741..d4df46cc9878 100644
--- a/src/channels/chat-meta.ts
+++ b/src/channels/chat-meta.ts
@@ -3,6 +3,7 @@
  *
  * Provides ordered channel metadata for setup, status, and selection surfaces.
  */
+import { expectDefined } from "@openclaw/normalization-core";
 import { buildChatChannelMetaById, type ChatChannelMeta } from "./chat-meta-shared.js";
 import { CHAT_CHANNEL_ORDER, type ChatChannelId } from "./ids.js";
 
@@ -26,6 +27,16 @@ export function listChatChannels(): ChatChannelMeta[] {
 /**
  * Returns metadata for one built-in chat channel id.
  */
-export function getChatChannelMeta(id: ChatChannelId): ChatChannelMeta {
+/** Drift-tolerant lookup: undefined when the id is missing from the bundled catalog. */
+export function findChatChannelMeta(id: ChatChannelId): ChatChannelMeta | undefined {
   return getChatChannelMetaById()[id];
 }
+
+/**
+ * Returns metadata for one built-in chat channel id.
+ * Shipped plugin-SDK contract: callers pass bundled ids, so absence is an invariant
+ * violation; drift-tolerant core paths use findChatChannelMeta instead.
+ */
+export function getChatChannelMeta(id: ChatChannelId): ChatChannelMeta {
+  return expectDefined(findChatChannelMeta(id), `chat channel meta for ${id}`);
+}
diff --git a/src/channels/message-access/runtime-identity.ts b/src/channels/message-access/runtime-identity.ts
index e929e5d14442..854a0bdec94b 100644
--- a/src/channels/message-access/runtime-identity.ts
+++ b/src/channels/message-access/runtime-identity.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /**
  * Channel ingress identity adapter helpers.
  *
@@ -112,7 +113,7 @@ export function createIdentityAdapter(
           return [
             adapterEntry({
               identity,
-              field: fields[0],
+              field: expectDefined(fields[0], "fields entry at 0"),
               fieldIndex: 0,
               entry,
               entryIndex,
diff --git a/src/channels/plugins/dm-access.ts b/src/channels/plugins/dm-access.ts
index 2ebfeff7adff..5fb4d347bbac 100644
--- a/src/channels/plugins/dm-access.ts
+++ b/src/channels/plugins/dm-access.ts
@@ -93,34 +93,49 @@ function readPath(entry: DmAccessRecord | null | undefined, path: readonly strin
 }
 
 function deletePath(entry: DmAccessRecord, path: readonly string[]): boolean {
-  if (path.length === 1) {
-    if (entry[path[0]] === undefined) {
-      return false;
-    }
-    delete entry[path[0]];
-    return true;
-  }
-  const parent = asObjectRecord(entry[path[0]]);
-  if (!parent || parent[path[1]] === undefined) {
+  const [head, tail] = path;
+  if (head === undefined) {
     return false;
   }
-  delete parent[path[1]];
+  if (path.length === 1) {
+    if (entry[head] === undefined) {
+      return false;
+    }
+    delete entry[head];
+    return true;
+  }
+  if (tail === undefined) {
+    return false;
+  }
+  const parent = asObjectRecord(entry[head]);
+  if (!parent || parent[tail] === undefined) {
+    return false;
+  }
+  delete parent[tail];
   if (Object.keys(parent).length === 0) {
-    delete entry[path[0]];
+    delete entry[head];
   } else {
-    entry[path[0]] = parent;
+    entry[head] = parent;
   }
   return true;
 }
 
 function writePath(entry: DmAccessRecord, path: readonly string[], value: unknown): void {
-  if (path.length === 1) {
-    entry[path[0]] = value;
+  const [head, tail] = path;
+  if (head === undefined) {
     return;
   }
-  const parent = asObjectRecord(entry[path[0]]) ? { ...(entry[path[0]] as DmAccessRecord) } : {};
-  parent[path[1]] = value;
-  entry[path[0]] = parent;
+  if (path.length === 1) {
+    entry[head] = value;
+    return;
+  }
+  if (tail === undefined) {
+    return;
+  }
+  const existingParent = asObjectRecord(entry[head]);
+  const parent = existingParent ? { ...existingParent } : {};
+  parent[tail] = value;
+  entry[head] = parent;
 }
 
 function allowFromListsMatch(left: unknown, right: unknown): boolean {
diff --git a/src/channels/plugins/setup-helpers.ts b/src/channels/plugins/setup-helpers.ts
index a60295b22f7d..490ab4531783 100644
--- a/src/channels/plugins/setup-helpers.ts
+++ b/src/channels/plugins/setup-helpers.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /**
  * Channel setup config mutation helpers.
  *
@@ -486,7 +487,9 @@ function resolveSingleAccountPromotionTarget(params: { channel: ChannelSectionBa
     );
   }
   const namedAccounts = Object.keys(accounts).filter(Boolean);
-  return namedAccounts.length === 1 ? namedAccounts[0] : DEFAULT_ACCOUNT_ID;
+  return namedAccounts.length === 1
+    ? expectDefined(namedAccounts[0], "named accounts entry at 0")
+    : DEFAULT_ACCOUNT_ID;
 }
 
 /**
diff --git a/src/channels/plugins/setup-wizard.ts b/src/channels/plugins/setup-wizard.ts
index d0f6d6735061..d7f3ece07380 100644
--- a/src/channels/plugins/setup-wizard.ts
+++ b/src/channels/plugins/setup-wizard.ts
@@ -562,8 +562,9 @@ export function buildChannelSetupWizardAdapterFromSetupWizard(params: {
         const allowFrom = wizard.allowFrom;
         // Allowlist resolution often needs the freshly entered credential, not
         // only the persisted config, because setup may not have been written yet.
+        const credentialInputKey = allowFrom.credentialInputKey ?? wizard.credentials[0]?.inputKey;
         const allowFromCredentialValue = normalizeOptionalString(
-          credentialValues[allowFrom.credentialInputKey ?? wizard.credentials[0]?.inputKey],
+          credentialInputKey === undefined ? undefined : credentialValues[credentialInputKey],
         );
         if (allowFrom.helpLines && allowFrom.helpLines.length > 0) {
           await prompter.note(
diff --git a/src/channels/registry.ts b/src/channels/registry.ts
index fd99558bd82b..de9874e36039 100644
--- a/src/channels/registry.ts
+++ b/src/channels/registry.ts
@@ -11,7 +11,7 @@ import {
   findRegisteredChannelPluginEntryById,
   listRegisteredChannelPluginEntries,
 } from "./registry-lookup.js";
-export { getChatChannelMeta } from "./chat-meta.js";
+export { findChatChannelMeta, getChatChannelMeta } from "./chat-meta.js";
 export { CHAT_CHANNEL_ORDER } from "./ids.js";
 export type { ChatChannelId } from "./ids.js";
 export { normalizeChatChannelId };
diff --git a/src/channels/streaming.ts b/src/channels/streaming.ts
index 476fa10293a2..e7dc8d12b938 100644
--- a/src/channels/streaming.ts
+++ b/src/channels/streaming.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Channel streaming config normalization and progress-draft formatting helpers.
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
 import { normalizeTrimmedStringList } from "@openclaw/normalization-core/string-normalization";
@@ -1139,7 +1140,10 @@ export function mergeChannelProgressDraftLine<TLine extends string | ChannelProg
       resolveProgressDraftLineMergeKeys(entry).some((entryKey) => lineKeys.includes(entryKey)),
     );
     if (existingIndex >= 0) {
-      const replacement = mergeProgressDraftLineUpdate(lines[existingIndex], line);
+      const replacement = mergeProgressDraftLineUpdate(
+        expectDefined(lines[existingIndex], "lines entry at existing index"),
+        line,
+      );
       if (replacement === lines[existingIndex]) {
         return lines;
       }
diff --git a/src/chat/canvas-render.ts b/src/chat/canvas-render.ts
index 04915dd36239..5b785dd9744a 100644
--- a/src/chat/canvas-render.ts
+++ b/src/chat/canvas-render.ts
@@ -1,5 +1,5 @@
 // Renders chat canvas payloads into text and metadata for transcript output.
-import { safeParseJson } from "@openclaw/normalization-core";
+import { expectDefined, safeParseJson } from "@openclaw/normalization-core";
 import { asFiniteNumber } from "@openclaw/normalization-core/number-coercion";
 import { asOptionalRecord } from "@openclaw/normalization-core/record-coerce";
 import { parseFenceSpans } from "../../packages/markdown-core/src/fences.js";
@@ -166,7 +166,7 @@ function previewFromShortcode(attrs: Record<string, string>): CanvasPreview | un
       kind: "canvas",
       surface,
       render: "url",
-      url: url ?? defaultCanvasEntryUrl(ref),
+      url: url ?? defaultCanvasEntryUrl(expectDefined(ref, "canvas reference")),
       ...(ref ? { viewId: ref } : {}),
       ...(title ? { title } : {}),
       ...(preferredHeight ? { preferredHeight } : {}),
diff --git a/src/cli/argv.ts b/src/cli/argv.ts
index 0df3e7195000..20e7e12d628a 100644
--- a/src/cli/argv.ts
+++ b/src/cli/argv.ts
@@ -229,8 +229,12 @@ export function normalizeGeneratedHelpCommandArgv(argv: string[]): string[] {
   ) {
     return argv;
   }
+  const [runtimePath, entryPath] = argv;
+  if (runtimePath === undefined || entryPath === undefined) {
+    return argv;
+  }
 
-  return [argv[0], argv[1], ...rootOptions, primary.value, target.value, "--help"];
+  return [runtimePath, entryPath, ...rootOptions, primary.value, target.value, "--help"];
 }
 
 export function normalizeRootHelpTargetArgv(argv: string[]): string[] {
@@ -241,16 +245,24 @@ export function normalizeRootHelpTargetArgv(argv: string[]): string[] {
   const { positionals, rootOptions, helpFlagIndex } = scan;
 
   const [help, target] = positionals;
+  // The --help flag must trail the LAST positional so nested targets like
+  // `help plugins list --help` still normalize (target is only the first one).
+  const lastPositional = positionals.at(-1);
   if (
     help?.value !== "help" ||
     !target ||
-    (helpFlagIndex !== null && helpFlagIndex !== positionals.at(-1)!.index + 1)
+    !lastPositional ||
+    (helpFlagIndex !== null && helpFlagIndex !== lastPositional.index + 1)
   ) {
     return argv;
   }
+  const [runtimePath, entryPath] = argv;
+  if (runtimePath === undefined || entryPath === undefined) {
+    return argv;
+  }
 
   const targetPath = positionals.slice(1).map((positional) => positional.value);
-  return [argv[0], argv[1], ...rootOptions, ...targetPath, "--help"];
+  return [runtimePath, entryPath, ...rootOptions, ...targetPath, "--help"];
 }
 
 export type NormalizeRootNoColorArgvOptions = {
@@ -328,7 +340,10 @@ export function normalizeRootNoColorArgv(
   const movedNoColorArgs: string[] = [];
   const nextArgs: string[] = [];
   for (let index = 0; index < remainingArgs.length; index += 1) {
-    const arg = remainingArgs[index];
+    const arg = remainingArgs.at(index);
+    if (arg === undefined) {
+      break;
+    }
     if (arg === FLAG_TERMINATOR) {
       nextArgs.push(...remainingArgs.slice(index));
       break;
@@ -363,7 +378,10 @@ export function normalizeRootLogLevelArgv(
   const movedLogLevelArgs: string[] = [];
   const nextArgs: string[] = [];
   for (let index = 0; index < remainingArgs.length; index += 1) {
-    const arg = remainingArgs[index];
+    const arg = remainingArgs.at(index);
+    if (arg === undefined) {
+      break;
+    }
     if (arg === FLAG_TERMINATOR) {
       nextArgs.push(...remainingArgs.slice(index));
       break;
@@ -398,7 +416,10 @@ export function getFlagValue(argv: string[], name: string): string | null | unde
   const args = argv.slice(2);
   let value: string | undefined;
   for (let i = 0; i < args.length; i += 1) {
-    const arg = args[i];
+    const arg = args.at(i);
+    if (arg === undefined) {
+      break;
+    }
     if (arg === FLAG_TERMINATOR) {
       break;
     }
diff --git a/src/cli/channel-auth.ts b/src/cli/channel-auth.ts
index 5582d06051ee..0305173fa8ea 100644
--- a/src/cli/channel-auth.ts
+++ b/src/cli/channel-auth.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Channel login/logout command helpers for local config and gateway reconciliation.
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { sanitizeForLog } from "../../packages/terminal-core/src/ansi.js";
@@ -74,7 +75,7 @@ function resolveConfiguredAuthChannelInput(cfg: OpenClawConfig, mode: ChannelAut
     .map((plugin) => plugin.id);
 
   if (configured.length === 1) {
-    return configured[0];
+    return expectDefined(configured[0], "configured entry at 0");
   }
   if (configured.length === 0) {
     throw new Error(
diff --git a/src/cli/command-path-policy.ts b/src/cli/command-path-policy.ts
index e17f8a9cb15f..7dc0a3bf1f28 100644
--- a/src/cli/command-path-policy.ts
+++ b/src/cli/command-path-policy.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Resolves CLI command path policy from the declarative command catalog.
 import { isGatewayConfigBypassCommandPath } from "../gateway/explicit-connection-policy.js";
 import { getCommandPathWithRootOptions } from "./argv.js";
@@ -58,7 +59,7 @@ export function resolveCliCatalogCommandPath(argv: string[]): string[] {
       bestMatch = entry.commandPath;
     }
   }
-  return bestMatch ? [...bestMatch] : [tokens[0]];
+  return bestMatch ? [...bestMatch] : [expectDefined(tokens[0], "tokens entry at 0")];
 }
 
 export function resolveCliNetworkProxyPolicy(argv: string[]): CliNetworkProxyPolicy {
diff --git a/src/cli/config-cli.ts b/src/cli/config-cli.ts
index cb9ffa70b97b..ebd7d3ceebea 100644
--- a/src/cli/config-cli.ts
+++ b/src/cli/config-cli.ts
@@ -1,5 +1,6 @@
 // Config CLI command implementation for get/set/unset/patch/validate and secret refs.
 import fs from "node:fs";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isRecord as isPlainRecord } from "@openclaw/normalization-core/record-coerce";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import {
@@ -282,7 +283,9 @@ function normalizeConfigMutationModelRefs(cfg: OpenClawConfig): OpenClawConfig {
 
 function normalizeConfigMutationExplicitSetPath(path: PathSegment[]): PathSegment[] {
   if (path.length >= 4 && path[0] === "agents" && path[1] === "defaults" && path[2] === "models") {
-    const normalizedModelId = normalizeAgentModelRefForConfig(path[3]);
+    const normalizedModelId = normalizeAgentModelRefForConfig(
+      expectDefined(path[3], "path entry at 3"),
+    );
     return normalizedModelId === path[3]
       ? path
       : [...path.slice(0, 3), normalizedModelId, ...path.slice(4)];
@@ -687,9 +690,12 @@ function setAtPath(
   value: unknown,
   options?: SetAtPathOptions,
 ): void {
+  const last = path.at(-1);
+  if (last === undefined) {
+    throw new Error("Config path must contain at least one segment");
+  }
   let current: unknown = root;
-  for (let i = 0; i < path.length - 1; i += 1) {
-    const segment = path[i];
+  for (const [i, segment] of path.slice(0, -1).entries()) {
     const next = path[i + 1];
     const nextIsIndex = shouldCreateArrayForMissingPathSegment({
       path,
@@ -723,7 +729,6 @@ function setAtPath(
     current = record[segment];
   }
 
-  const last = path[path.length - 1];
   if (Array.isArray(current)) {
     if (!isIndexSegment(last)) {
       throw new Error(`Expected numeric index for array segment "${last}"`);
@@ -892,9 +897,12 @@ function assertNonDestructiveReplacement(params: {
 type UnsetAtPathResult = { removed: true; leafContainer: "array" | "object" } | { removed: false };
 
 function unsetAtPath(root: Record<string, unknown>, path: PathSegment[]): UnsetAtPathResult {
+  const last = path.at(-1);
+  if (last === undefined) {
+    return { removed: false };
+  }
   let current: unknown = root;
-  for (let i = 0; i < path.length - 1; i += 1) {
-    const segment = path[i];
+  for (const segment of path.slice(0, -1)) {
     if (!current || typeof current !== "object") {
       return { removed: false };
     }
@@ -916,7 +924,6 @@ function unsetAtPath(root: Record<string, unknown>, path: PathSegment[]): UnsetA
     current = record[segment];
   }
 
-  const last = path[path.length - 1];
   if (Array.isArray(current)) {
     if (!isIndexSegment(last)) {
       return { removed: false };
diff --git a/src/cli/container-target.ts b/src/cli/container-target.ts
index c56b28ec07ce..0f410af8dd5e 100644
--- a/src/cli/container-target.ts
+++ b/src/cli/container-target.ts
@@ -1,6 +1,7 @@
 // CLI container targeting: parse --container and re-exec the command inside Docker/Podman.
 import { spawnSync } from "node:child_process";
 import { isIP } from "node:net";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { consumeRootOptionToken, FLAG_TERMINATOR } from "../infra/cli-root-options.js";
 import { resolveCliArgvInvocation } from "./argv-invocation.js";
@@ -124,7 +125,7 @@ function resolveRunningContainer(params: {
       `Container "${params.containerName}" is running under multiple runtimes (${runtimes}); use a unique container name.`,
     );
   }
-  return matches[0];
+  return expectDefined(matches[0], "matches capture group 0");
 }
 
 function buildContainerExecArgs(params: {
@@ -196,7 +197,7 @@ function isLoopbackProxyHostname(hostname: string): boolean {
   if (!mapped) {
     return false;
   }
-  const high = Number.parseInt(mapped[1], 16);
+  const high = Number.parseInt(expectDefined(mapped[1], "mapped capture group 1"), 16);
   return Number.isInteger(high) && high >= 0x7f00 && high <= 0x7fff;
 }
 
diff --git a/src/cli/daemon-cli/lifecycle.ts b/src/cli/daemon-cli/lifecycle.ts
index d0a0a6af7f9f..3ffc8eda1f9c 100644
--- a/src/cli/daemon-cli/lifecycle.ts
+++ b/src/cli/daemon-cli/lifecycle.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Gateway service lifecycle runners, including unmanaged-process fallbacks and restart health checks.
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { theme } from "../../../packages/terminal-core/src/theme.js";
@@ -252,7 +253,7 @@ async function restartGatewayWithoutServiceManager(
     reason: "gateway.restart",
     ...(restartIntent ? { intent: restartIntent } : {}),
   });
-  signalVerifiedGatewayPidSync(pids[0], "SIGUSR1");
+  signalVerifiedGatewayPidSync(expectDefined(pids[0], "pids entry at 0"), "SIGUSR1");
   return {
     result: "restarted" as const,
     message: `Gateway restart signal sent to unmanaged process on port ${port}: ${pids[0]}.`,
diff --git a/src/cli/exec-approvals-cli.ts b/src/cli/exec-approvals-cli.ts
index 02a1807edd35..5126af90fd61 100644
--- a/src/cli/exec-approvals-cli.ts
+++ b/src/cli/exec-approvals-cli.ts
@@ -1,5 +1,6 @@
 // CLI for reading and mutating exec approval allowlists locally, via gateway, or via node.
 import fs from "node:fs/promises";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import type { Command } from "commander";
@@ -342,7 +343,7 @@ async function saveSnapshotTargeted(params: SaveSnapshotTargetedParams): Promise
 function formatCliError(err: unknown): string {
   const msg = formatErrorMessage(err);
   const firstLine = msg.includes("\n") ? msg.split("\n")[0] : msg;
-  const safe = sanitizeForLog(firstLine);
+  const safe = sanitizeForLog(expectDefined(firstLine, "exec approvals cli first line"));
   return safe.length > 300 ? `${truncateUtf16Safe(safe, 300)}...` : safe;
 }
 
diff --git a/src/cli/gateway-cli/run.ts b/src/cli/gateway-cli/run.ts
index fc96d533b60f..d0f3f4f72e54 100644
--- a/src/cli/gateway-cli/run.ts
+++ b/src/cli/gateway-cli/run.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs";
 import { request } from "node:http";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeOptionalLowercaseString,
   normalizeOptionalString,
@@ -183,7 +184,7 @@ function formatModeErrorList(modes: readonly string[]): string {
     return "";
   }
   if (quoted.length === 1) {
-    return quoted[0];
+    return expectDefined(quoted[0], "quoted entry at 0");
   }
   if (quoted.length === 2) {
     return `${quoted[0]} or ${quoted[1]}`;
diff --git a/src/cli/lobster-art.ts b/src/cli/lobster-art.ts
index 3b10a16577cb..01b37d2ee5e8 100644
--- a/src/cli/lobster-art.ts
+++ b/src/cli/lobster-art.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // The Control UI lobster pet has a CLI cousin: on roughly one day in sixteen
 // the interactive banner gains a tiny ASCII lobster. The day comes from the
 // shared lobster-day hash (the sidebar pet dresses up on the same days), so
@@ -22,5 +23,8 @@ export function pickCliLobsterArt(now: Date, env: NodeJS.ProcessEnv = process.en
   if (!isLobsterDay(now)) {
     return null;
   }
-  return LOBSTER_ARTS[(lobsterDayHash(now) >>> 8) % LOBSTER_ARTS.length];
+  return expectDefined(
+    LOBSTER_ARTS[(lobsterDayHash(now) >>> 8) % LOBSTER_ARTS.length],
+    "lobster arts entry at (lobster day hash(now) >>> 8) % lobster arts.length",
+  );
 }
diff --git a/src/cli/logs-cli.runtime.ts b/src/cli/logs-cli.runtime.ts
index 722adbb5f19c..e559dcd37507 100644
--- a/src/cli/logs-cli.runtime.ts
+++ b/src/cli/logs-cli.runtime.ts
@@ -1,5 +1,6 @@
 // Runtime helpers for bounded subprocess log tails and service runtime lookups.
 import { spawn } from "node:child_process";
+import { expectDefined } from "@openclaw/normalization-core";
 
 export { buildGatewayConnectionDetails } from "../gateway/call.js";
 export { resolveGatewaySystemdServiceName } from "../daemon/constants.js";
@@ -15,7 +16,7 @@ function appendByteTail(tail: ByteTail, chunk: Buffer, maxBytes: number): void {
   tail.chunks.push(chunk);
   tail.bytes += chunk.length;
   while (tail.bytes > maxBytes && tail.chunks.length > 0) {
-    const first = tail.chunks[0];
+    const first = expectDefined(tail.chunks[0], "chunks entry at 0");
     const overflow = tail.bytes - maxBytes;
     if (first.length <= overflow) {
       tail.chunks.shift();
@@ -36,7 +37,10 @@ function decodeUtf8Tail(tail: ByteTail): string {
   // A byte cap can cut the leading code point. Skip only its continuation
   // bytes so decoding cannot invent a replacement character at the boundary.
   let offset = 0;
-  while (offset < buffer.length && (buffer[offset] & 0xc0) === 0x80) {
+  while (
+    offset < buffer.length &&
+    (expectDefined(buffer[offset], "buffer entry at offset") & 0xc0) === 0x80
+  ) {
     offset += 1;
   }
   return buffer.subarray(offset).toString("utf8");
diff --git a/src/cli/mcp-cli.ts b/src/cli/mcp-cli.ts
index 26ecc66bf3c8..f7f64846c3ff 100644
--- a/src/cli/mcp-cli.ts
+++ b/src/cli/mcp-cli.ts
@@ -2,6 +2,7 @@
 import { constants as fsConstants } from "node:fs";
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { parseStrictFiniteNumber } from "@openclaw/normalization-core/number-coercion";
 import {
   normalizeLowercaseStringOrEmpty,
@@ -550,7 +551,7 @@ async function probeMcpServersOrFail(params: {
   try {
     const result = formatMcpProbeResult(await runtime.getCatalog());
     if (result.diagnostics.length > 0) {
-      const first = result.diagnostics[0];
+      const first = expectDefined(result.diagnostics[0], "diagnostics entry at 0");
       fail(`MCP probe failed for "${first.serverName}" in ${params.path}: ${first.message}`);
     }
     for (const name of Object.keys(params.servers)) {
diff --git a/src/cli/parse-duration.ts b/src/cli/parse-duration.ts
index 64342e083cdf..11ff755e8ff8 100644
--- a/src/cli/parse-duration.ts
+++ b/src/cli/parse-duration.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Duration parser shared by CLI flags, command directives, and config-backed timing values.
 import {
   normalizeLowercaseStringOrEmpty,
@@ -46,7 +47,10 @@ export function parseDurationMs(raw: string, opts?: DurationMsParseOptions): num
       throw invalidDuration(raw);
     }
     const unit = (single[2] ?? opts?.defaultUnit ?? "ms") as "ms" | "s" | "m" | "h" | "d";
-    return roundSafeDurationMs(raw, value * DURATION_MULTIPLIERS[unit]);
+    return roundSafeDurationMs(
+      raw,
+      value * expectDefined(DURATION_MULTIPLIERS[unit], "duration multipliers entry at unit"),
+    );
   }
 
   // Composite form (e.g. "1h30m", "2m500ms"); each token must include a unit.
diff --git a/src/cli/plugin-install-config-policy.ts b/src/cli/plugin-install-config-policy.ts
index 10e4d27b4cd2..b8f81bf7421b 100644
--- a/src/cli/plugin-install-config-policy.ts
+++ b/src/cli/plugin-install-config-policy.ts
@@ -180,7 +180,10 @@ function resolvePluginInstallArgvRequest(commandPath: string[], argv: string[])
   let rawSpec: string | null = null;
   let marketplace: string | undefined;
   for (let index = 0; index < tokens.length; index += 1) {
-    const token = tokens[index];
+    const token = tokens.at(index);
+    if (token === undefined) {
+      break;
+    }
     if (token.startsWith("--marketplace=")) {
       marketplace = token.slice("--marketplace=".length);
       continue;
diff --git a/src/cli/plugins-update-selection.ts b/src/cli/plugins-update-selection.ts
index 0899178f9b1f..03895b04dffc 100644
--- a/src/cli/plugins-update-selection.ts
+++ b/src/cli/plugins-update-selection.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Plugin and hook-pack update selectors for id and npm-spec command inputs.
 import type { HookInstallRecord } from "../config/types.hooks.js";
 import type { PluginInstallRecord } from "../config/types.plugins.js";
@@ -35,7 +36,7 @@ export function resolvePluginUpdateSelection(params: {
     return { pluginIds: [params.rawId] };
   }
 
-  const [pluginId] = matches[0];
+  const [pluginId] = expectDefined(matches[0], "matches capture group 0");
   if (!pluginId) {
     return { pluginIds: [params.rawId] };
   }
@@ -83,7 +84,7 @@ export function resolveHookPackUpdateSelection(params: {
     return { hookIds: [] };
   }
 
-  const [hookId] = matches[0];
+  const [hookId] = expectDefined(matches[0], "matches capture group 0");
   if (!hookId) {
     return { hookIds: [] };
   }
diff --git a/src/cli/profile.ts b/src/cli/profile.ts
index 92a22d42a64c..b354badcf4f3 100644
--- a/src/cli/profile.ts
+++ b/src/cli/profile.ts
@@ -40,7 +40,7 @@ export function parseCliProfileArgs(argv: string[]): CliProfileParseResult {
       const [primary, secondary] = resolveCliArgvInvocation(out).commandPath;
       if (primary === "qa" && secondary === "matrix") {
         out.push(arg);
-        if (consumedNext) {
+        if (consumedNext && next !== undefined) {
           out.push(next);
         }
         return { kind: "handled", consumedNext };
diff --git a/src/cli/program/action-reparse.ts b/src/cli/program/action-reparse.ts
index 3527eb817900..8614c58e2346 100644
--- a/src/cli/program/action-reparse.ts
+++ b/src/cli/program/action-reparse.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Reparse support for lazy commands after their placeholder has been replaced.
 import type { Command, Option } from "commander";
 import { buildParseArgv } from "../argv.js";
@@ -26,7 +27,10 @@ function buildFallbackArgv(program: Command, actionCommand: Command | undefined)
   return [
     ...commandPath.slice(0, -1),
     ...parentOptionArgs,
-    commandPath[commandPath.length - 1],
+    expectDefined(
+      commandPath[commandPath.length - 1],
+      "command path entry at command path.length 1",
+    ),
     ...actionArgsList,
   ];
 }
diff --git a/src/cli/program/route-args.ts b/src/cli/program/route-args.ts
index 6da5bc0c7405..8c8483c70bc0 100644
--- a/src/cli/program/route-args.ts
+++ b/src/cli/program/route-args.ts
@@ -32,7 +32,7 @@ function parseRepeatedFlagValues(argv: string[], name: string): string[] | null
     }
     if (arg === name) {
       const next = args[i + 1];
-      if (!isValueToken(next)) {
+      if (next === undefined || !isValueToken(next)) {
         // Invalid fast-path shapes fall back to Commander so its normal errors and help text win.
         return null;
       }
diff --git a/src/cli/proxy-cli.runtime.ts b/src/cli/proxy-cli.runtime.ts
index 40639db181b1..4c74169cd8fa 100644
--- a/src/cli/proxy-cli.runtime.ts
+++ b/src/cli/proxy-cli.runtime.ts
@@ -2,6 +2,7 @@
 import { spawn } from "node:child_process";
 import { randomUUID } from "node:crypto";
 import process from "node:process";
+import { expectDefined } from "@openclaw/normalization-core";
 import { colorize, isRich, theme } from "../../packages/terminal-core/src/theme.js";
 import { getRuntimeConfig } from "../config/config.js";
 import {
@@ -100,7 +101,7 @@ export async function runDebugProxyRunCommand(opts: {
   });
   try {
     await new Promise<void>((resolve, reject) => {
-      const child = spawn(command, args, {
+      const child = spawn(expectDefined(command, "proxy cli.runtime command"), args, {
         stdio: "inherit",
         env: childEnv,
         cwd: process.cwd(),
diff --git a/src/cli/tagline.ts b/src/cli/tagline.ts
index e08610e7f885..5d7cd20f327c 100644
--- a/src/cli/tagline.ts
+++ b/src/cli/tagline.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // CLI tagline selection helpers, including deterministic random/default/holiday modes.
 import { parseStrictNonNegativeInteger } from "../infra/parse-finite-number.js";
 
@@ -321,13 +322,13 @@ export function pickTagline(options: TaglineOptions = {}): string {
     const parsed = parseStrictNonNegativeInteger(override);
     if (parsed !== undefined) {
       const pool = TAGLINES.length > 0 ? TAGLINES : [DEFAULT_TAGLINE];
-      return pool[parsed % pool.length];
+      return expectDefined(pool[parsed % pool.length], "pool entry at parsed % pool.length");
     }
   }
   const pool = activeTaglines(options);
   const rand = options.random ?? Math.random;
   const index = Math.floor(rand() * pool.length) % pool.length;
-  return pool[index];
+  return expectDefined(pool[index], "pool entry at index");
 }
 
 export { DEFAULT_TAGLINE };
diff --git a/src/commands/agents.bindings.ts b/src/commands/agents.bindings.ts
index 80f0f9818549..63e528e3c4cf 100644
--- a/src/commands/agents.bindings.ts
+++ b/src/commands/agents.bindings.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Pure helpers for parsing, adding, removing, and generating agent route bindings.
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { normalizeSortedUniqueStringEntries } from "@openclaw/normalization-core/string-normalization";
@@ -327,7 +328,11 @@ export function parseBindingSpecs(params: {
     }
     const channel = normalizeBindingChannelId(channelRaw, params.config);
     if (!channel) {
-      errors.push(formatUnknownChannelMessage({ channel: channelRaw }));
+      errors.push(
+        formatUnknownChannelMessage({
+          channel: expectDefined(channelRaw, "agents.bindings channel raw"),
+        }),
+      );
       continue;
     }
     let accountId: string | undefined = accountRaw?.trim();
diff --git a/src/commands/agents.commands.identity.ts b/src/commands/agents.commands.identity.ts
index ef5d0de84f2a..a82d3499ff0a 100644
--- a/src/commands/agents.commands.identity.ts
+++ b/src/commands/agents.commands.identity.ts
@@ -1,13 +1,14 @@
 // Implements identity metadata updates for configured agents.
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { resolveAgentWorkspaceDir, resolveDefaultAgentId } from "../agents/agent-scope.js";
 import { identityHasValues, parseIdentityMarkdown } from "../agents/identity-file.js";
 import { DEFAULT_IDENTITY_FILENAME } from "../agents/workspace.js";
 import { replaceConfigFile } from "../config/config.js";
 import { logConfigUpdated } from "../config/logging.js";
-import type { IdentityConfig } from "../config/types.js";
+import type { AgentConfig, IdentityConfig } from "../config/types.js";
 import { normalizeAgentId } from "../routing/session-key.js";
 import { type RuntimeEnv, writeRuntimeJson } from "../runtime.js";
 import { defaultRuntime } from "../runtime.js";
@@ -163,9 +164,11 @@ export async function agentsSetIdentityCommand(
     return;
   }
 
+  const resolvedAgentId = expectDefined(agentId, "agent id");
   const list = listAgentEntries(cfg);
-  const index = findAgentEntryIndex(list, agentId);
-  const base = index >= 0 ? list[index] : { id: agentId };
+  const index = findAgentEntryIndex(list, resolvedAgentId);
+  const base: AgentConfig =
+    index >= 0 ? expectDefined(list[index], "agent config") : { id: resolvedAgentId };
   const nextIdentity: IdentityConfig = {
     ...base.identity,
     ...incomingIdentity,
@@ -181,7 +184,7 @@ export async function agentsSetIdentityCommand(
     nextList[index] = nextEntry;
   } else {
     const defaultId = normalizeAgentId(resolveDefaultAgentId(cfg));
-    if (nextList.length === 0 && agentId !== defaultId) {
+    if (nextList.length === 0 && resolvedAgentId !== defaultId) {
       nextList.push({ id: defaultId });
     }
     nextList.push(nextEntry);
diff --git a/src/commands/agents.config.ts b/src/commands/agents.config.ts
index 5e24f43de388..d0e41d312e46 100644
--- a/src/commands/agents.config.ts
+++ b/src/commands/agents.config.ts
@@ -126,7 +126,7 @@ export function applyAgentConfig(
   const name = params.name?.trim();
   const list = listAgentEntries(cfg);
   const index = findAgentEntryIndex(list, agentId);
-  const base = index >= 0 ? list[index] : { id: agentId };
+  const base = (index >= 0 ? list[index] : undefined) ?? { id: agentId };
   const mergedIdentity = params.identity ? { ...base.identity, ...params.identity } : undefined;
   const nextEntry: AgentEntry = {
     ...base,
diff --git a/src/commands/auth-choice-prompt.ts b/src/commands/auth-choice-prompt.ts
index 5a088060e6b0..d3d25cc74bf8 100644
--- a/src/commands/auth-choice-prompt.ts
+++ b/src/commands/auth-choice-prompt.ts
@@ -1,5 +1,6 @@
 // Interactive grouped auth-choice prompt used by onboarding and agent setup.
 import { normalizeProviderId } from "@openclaw/model-catalog-core/provider-id";
+import { expectDefined } from "@openclaw/normalization-core";
 import type { AuthProfileStore } from "../agents/auth-profiles/types.js";
 import { resolveAgentModelPrimaryValue } from "../config/model-input.js";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
@@ -90,7 +91,7 @@ export async function promptAuthChoiceGrouped(
         } satisfies WizardSelectOption<KeepCurrentAuthChoice>)
       : undefined;
     if (group.options.length === 1 && !keepCurrentOption) {
-      return group.options[0].value;
+      return expectDefined(group.options[0], "options entry at 0").value;
     }
     return (await params.prompter.select({
       message: `${group.label} auth method`,
diff --git a/src/commands/daemon-install-plan.shared.ts b/src/commands/daemon-install-plan.shared.ts
index adb366cc869a..e9231f408810 100644
--- a/src/commands/daemon-install-plan.shared.ts
+++ b/src/commands/daemon-install-plan.shared.ts
@@ -12,7 +12,11 @@ import type { GatewayDaemonRuntime } from "./daemon-runtime.js";
 export function resolveGatewayDevMode(argv: string[] = process.argv): boolean {
   const entry = argv[1];
   const normalizedEntry = entry?.replaceAll("\\", "/");
-  return normalizedEntry?.includes("/src/") && normalizedEntry.endsWith(".ts");
+  return (
+    normalizedEntry !== undefined &&
+    normalizedEntry.includes("/src/") &&
+    normalizedEntry.endsWith(".ts")
+  );
 }
 
 /** Resolve dev-mode and Node path inputs for daemon service install planning. */
diff --git a/src/commands/doctor-disk-space.ts b/src/commands/doctor-disk-space.ts
index 10ab2e17a9df..e29f1ccf730a 100644
--- a/src/commands/doctor-disk-space.ts
+++ b/src/commands/doctor-disk-space.ts
@@ -1,6 +1,6 @@
 // Doctor contribution for low disk space around the OpenClaw state directory.
 import os from "node:os";
-import { formatByteSize } from "@openclaw/normalization-core";
+import { expectDefined, formatByteSize } from "@openclaw/normalization-core";
 import { note } from "../../packages/terminal-core/src/note.js";
 import type { OpenClawConfig } from "../config/config.js";
 import { resolveStateDir } from "../config/paths.js";
@@ -117,7 +117,7 @@ export function collectDiskSpaceHealthFindings(
     {
       checkId: DISK_SPACE_CHECK_ID,
       severity: "warning",
-      message: message.replace(/^- /, ""),
+      message: expectDefined(message, "disk-space warning message").replace(/^- /, ""),
       path: result.stateDir,
       target: formatBytes(result.availableBytes),
       requirement:
diff --git a/src/commands/doctor-session-sqlite.ts b/src/commands/doctor-session-sqlite.ts
index dc29e558a75a..fb74627e5f92 100644
--- a/src/commands/doctor-session-sqlite.ts
+++ b/src/commands/doctor-session-sqlite.ts
@@ -310,8 +310,12 @@ function resolveFullyCoveredLegacyStorePaths(
     targetsByStore.set(storePath, [...(targetsByStore.get(storePath) ?? []), target]);
   }
   for (const [storePath, storeTargets] of targetsByStore) {
+    const [firstStoreTarget] = storeTargets;
+    if (!firstStoreTarget) {
+      continue;
+    }
     const issues: DoctorSessionSqliteIssue[] = [];
-    const records = readLegacySessionRecords(storeTargets[0], issues);
+    const records = readLegacySessionRecords(firstStoreTarget, issues);
     const coversEveryRecord = records.every((record) =>
       storeTargets.some(
         (target) =>
@@ -704,7 +708,11 @@ function archiveImportedLegacySessionStores(
     if (entries.some((entry) => blockingIssueCount(entry.report) > 0)) {
       continue;
     }
-    const archivePath = archiveLegacySessionStore(entries[0].target, entries[0].report, activeRun);
+    const [firstEntry] = entries;
+    if (!firstEntry) {
+      continue;
+    }
+    const archivePath = archiveLegacySessionStore(firstEntry.target, firstEntry.report, activeRun);
     if (!archivePath) {
       continue;
     }
diff --git a/src/commands/doctor-state-integrity.ts b/src/commands/doctor-state-integrity.ts
index 91e1305afbb8..2dd29b3d8149 100644
--- a/src/commands/doctor-state-integrity.ts
+++ b/src/commands/doctor-state-integrity.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { asNullableObjectRecord } from "@openclaw/normalization-core/record-coerce";
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
 import { uniqueStrings } from "@openclaw/normalization-core/string-normalization";
@@ -434,9 +435,9 @@ function parseLinuxMountInfo(rawMountInfo: string): LinuxMountInfoEntry[] {
     }
 
     entries.push({
-      mountPoint: decodeMountInfoPath(leftFields[4]),
-      fsType: rightFields[0],
-      source: decodeMountInfoPath(rightFields[1]),
+      mountPoint: decodeMountInfoPath(expectDefined(leftFields[4], "left fields entry at 4")),
+      fsType: expectDefined(rightFields[0], "right fields entry at 0"),
+      source: decodeMountInfoPath(expectDefined(rightFields[1], "right fields entry at 1")),
     });
   }
   return entries;
diff --git a/src/commands/doctor/shared/allowfrom-fallback-migration.ts b/src/commands/doctor/shared/allowfrom-fallback-migration.ts
index aab7e1f346ac..12067284ca3f 100644
--- a/src/commands/doctor/shared/allowfrom-fallback-migration.ts
+++ b/src/commands/doctor/shared/allowfrom-fallback-migration.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Doctor migration from legacy DM allowFrom fallback to explicit groupAllowFrom lists.
 import { normalizeUniqueStringEntries } from "@openclaw/normalization-core/string-normalization";
 import { resolveChannelDmAllowFrom } from "../../../channels/plugins/dm-access.js";
@@ -87,10 +88,11 @@ function schemaAllowsConfigPath(schema: unknown, path: SchemaPath): boolean {
     return allOf.every((branch) => schemaAllowsConfigPath(branch, path));
   }
 
-  const [segment, ...rest] = path;
+  const segment = expectDefined(path[0], "schema path segment");
+  const rest = path.slice(1);
   const properties = asObjectRecord(node.properties);
   if (segment !== ACCOUNT_SCHEMA_WILDCARD && properties && Object.hasOwn(properties, segment)) {
-    return schemaAllowsConfigPath(properties[segment], rest);
+    return schemaAllowsConfigPath(expectDefined(properties[segment], "schema property"), rest);
   }
 
   const additionalProperties = node.additionalProperties;
diff --git a/src/commands/doctor/shared/stale-oauth-profile-shadows.ts b/src/commands/doctor/shared/stale-oauth-profile-shadows.ts
index a57c5c118741..707065607bcb 100644
--- a/src/commands/doctor/shared/stale-oauth-profile-shadows.ts
+++ b/src/commands/doctor/shared/stale-oauth-profile-shadows.ts
@@ -1,6 +1,7 @@
 // Doctor cleanup for per-agent OAuth profiles shadowing fresher main-agent credentials.
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isRecord } from "@openclaw/normalization-core/record-coerce";
 import {
   resolveAgentDir,
@@ -216,7 +217,9 @@ function removeStaleProfilesFromStore(params: {
 }
 
 function formatProfileList(profileIds: string[]): string {
-  return profileIds.length === 1 ? profileIds[0] : `${profileIds.length} profiles`;
+  return profileIds.length === 1
+    ? expectDefined(profileIds[0], "profile ids entry at 0")
+    : `${profileIds.length} profiles`;
 }
 
 async function repairStaleOAuthProfilesForAgent(params: {
diff --git a/src/commands/health-format.ts b/src/commands/health-format.ts
index 84c149bce9e9..1cc6b4a64c1d 100644
--- a/src/commands/health-format.ts
+++ b/src/commands/health-format.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Formatting helpers for `openclaw health` failures and channel summaries. */
 import { asNullableRecord } from "@openclaw/normalization-core/record-coerce";
 import { sanitizeTerminalText } from "../../packages/terminal-core/src/safe-text.js";
@@ -173,6 +174,7 @@ export const formatHealthChannelLines = (
         : (filteredSummaries ?? (channelSummary.accounts ? Object.values(accountSummaries) : []));
     const baseSummary =
       filteredSummaries && filteredSummaries.length > 0 ? filteredSummaries[0] : channelSummary;
+    const selectedSummary = expectDefined(baseSummary, "channel health summary");
     const botUsernames = listSummaries
       ? listSummaries
           .map((account) => {
@@ -183,10 +185,11 @@ export const formatHealthChannelLines = (
           .filter((value): value is string => Boolean(value))
       : [];
     const statusState =
-      typeof baseSummary.statusState === "string" ? baseSummary.statusState : null;
+      typeof selectedSummary.statusState === "string" ? selectedSummary.statusState : null;
     if (statusState) {
       if (statusState === "linked") {
-        const authAgeMs = typeof baseSummary.authAgeMs === "number" ? baseSummary.authAgeMs : null;
+        const authAgeMs =
+          typeof selectedSummary.authAgeMs === "number" ? selectedSummary.authAgeMs : null;
         const authLabel = authAgeMs != null ? ` (auth age ${Math.round(authAgeMs / 60000)}m)` : "";
         lines.push(`${label}: ${formatChannelStatusState(statusState)}${authLabel}`);
       } else {
@@ -195,10 +198,11 @@ export const formatHealthChannelLines = (
       continue;
     }
 
-    const linked = typeof baseSummary.linked === "boolean" ? baseSummary.linked : null;
+    const linked = typeof selectedSummary.linked === "boolean" ? selectedSummary.linked : null;
     if (linked !== null) {
       if (linked) {
-        const authAgeMs = typeof baseSummary.authAgeMs === "number" ? baseSummary.authAgeMs : null;
+        const authAgeMs =
+          typeof selectedSummary.authAgeMs === "number" ? selectedSummary.authAgeMs : null;
         const authLabel = authAgeMs != null ? ` (auth age ${Math.round(authAgeMs / 60000)}m)` : "";
         lines.push(`${label}: linked${authLabel}`);
       } else {
@@ -207,7 +211,8 @@ export const formatHealthChannelLines = (
       continue;
     }
 
-    const configured = typeof baseSummary.configured === "boolean" ? baseSummary.configured : null;
+    const configured =
+      typeof selectedSummary.configured === "boolean" ? selectedSummary.configured : null;
     if (configured === false) {
       lines.push(`${label}: not configured`);
       continue;
@@ -233,7 +238,9 @@ export const formatHealthChannelLines = (
       continue;
     }
 
-    const probeLine = formatProbeLine(baseSummary.probe, { botUsernames });
+    const probeLine = formatProbeLine(selectedSummary.probe, {
+      botUsernames,
+    });
     if (probeLine) {
       lines.push(`${label}: ${probeLine}`);
       continue;
diff --git a/src/commands/health.ts b/src/commands/health.ts
index 547901683d3d..f5325393339c 100644
--- a/src/commands/health.ts
+++ b/src/commands/health.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Collects and renders gateway health for channels, agents, plugins, and sessions. */
 import { resolveTimerTimeoutMs } from "@openclaw/normalization-core/number-coercion";
 import { asNullableRecord } from "@openclaw/normalization-core/record-coerce";
@@ -700,7 +701,11 @@ export async function getHealthSnapshot(params?: {
       accountSummaries[preferredAccountId] ??
       accountSummaries[defaultAccountId] ??
       accountSummaries[accountIdsToProbe[0] ?? preferredAccountId];
-    const fallbackSummary = defaultSummary ?? accountSummaries[Object.keys(accountSummaries)[0]];
+    const fallbackSummary =
+      defaultSummary ??
+      accountSummaries[
+        expectDefined(Object.keys(accountSummaries)[0], "object.keys(account summaries) entry at 0")
+      ];
     if (fallbackSummary) {
       channels[plugin.id] = {
         ...fallbackSummary,
diff --git a/src/commands/migrate/selection.ts b/src/commands/migrate/selection.ts
index 6897b30b3740..2272cbf4c53e 100644
--- a/src/commands/migrate/selection.ts
+++ b/src/commands/migrate/selection.ts
@@ -1,5 +1,6 @@
 /** Selection helpers for filtering migration plan items before apply. */
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isRecord } from "@openclaw/normalization-core/record-coerce";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { uniqueStrings } from "@openclaw/normalization-core/string-normalization";
@@ -130,7 +131,9 @@ function resolveSelectedMigrationItemIds(params: {
     const available = params.items
       .map(params.formatSelectionLabel)
       .toSorted((a, b) => a.localeCompare(b));
-    const titleKind = params.kindLabel[0].toUpperCase() + params.kindLabel.slice(1);
+    const titleKind =
+      expectDefined(params.kindLabel[0], "kind label entry at 0").toUpperCase() +
+      params.kindLabel.slice(1);
     const parts: string[] = [];
     if (unknownRefs.length > 0) {
       parts.push(
diff --git a/src/commands/models/auth.ts b/src/commands/models/auth.ts
index 3147b493ec0c..01a6698564a3 100644
--- a/src/commands/models/auth.ts
+++ b/src/commands/models/auth.ts
@@ -7,6 +7,7 @@ import {
   select as clackSelect,
   text as clackText,
 } from "@clack/prompts";
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveExpiresAtMsFromDurationMs } from "@openclaw/normalization-core/number-coercion";
 import {
   normalizeOptionalString,
@@ -999,7 +1000,7 @@ export function resolveLoginProfiles(params: {
   }
 
   const [profile] = params.result.profiles;
-  return [{ ...profile, profileId: requestedProfileId }];
+  return [{ ...expectDefined(profile, "auth profile"), profileId: requestedProfileId }];
 }
 
 function maybeLogOpenAICodexNativeSearchTip(runtime: RuntimeEnv, providerId: string) {
diff --git a/src/commands/models/list.probe.ts b/src/commands/models/list.probe.ts
index 43df135584d5..31d9cee8283b 100644
--- a/src/commands/models/list.probe.ts
+++ b/src/commands/models/list.probe.ts
@@ -1,6 +1,7 @@
 /** Auth probe planning and execution helpers for model diagnostics. */
 import crypto from "node:crypto";
 import fs from "node:fs/promises";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeUniqueStringEntries } from "@openclaw/normalization-core/string-normalization";
 import {
   resolveAgentDir,
@@ -194,7 +195,7 @@ function selectProbeModel(params: {
   const { provider, candidates, catalog } = params;
   const direct = candidates.get(provider);
   if (direct && direct.length > 0) {
-    return { provider, model: direct[0] };
+    return { provider, model: expectDefined(direct[0], "direct entry at 0") };
   }
   const fromCatalog = catalog
     .map((entry, index) => ({ entry, index }))
@@ -601,7 +602,7 @@ async function runTargetsWithConcurrency(params: {
       if (index >= targets.length) {
         return;
       }
-      const target = targets[index];
+      const target = expectDefined(targets[index], "targets entry at index");
       onProgress?.({
         completed,
         total: targets.length,
diff --git a/src/commands/models/list.provider-catalog.ts b/src/commands/models/list.provider-catalog.ts
index 0a923874e398..f18fc43d21b2 100644
--- a/src/commands/models/list.provider-catalog.ts
+++ b/src/commands/models/list.provider-catalog.ts
@@ -1,6 +1,7 @@
 /** Provider plugin catalog loading for model-list output. */
 import { createHash } from "node:crypto";
 import { normalizeProviderId } from "@openclaw/model-catalog-core/provider-id";
+import { expectDefined } from "@openclaw/normalization-core";
 import { sortUniqueStrings } from "@openclaw/normalization-core/string-normalization";
 import { loadAuthProfileStoreWithoutExternalProfiles } from "../../agents/auth-profiles/store.js";
 import {
@@ -47,7 +48,11 @@ function buildProviderCatalogEnvCacheFingerprint(env: NodeJS.ProcessEnv): string
   const entries = Object.entries(env)
     .filter((entry): entry is [string, string] => entry[1] !== undefined)
     .map(([key, value]) => [key, createHash("sha256").update(value).digest("hex")])
-    .toSorted(([left], [right]) => left.localeCompare(right));
+    .toSorted(([left], [right]) =>
+      expectDefined(left, "list.provider catalog left").localeCompare(
+        expectDefined(right, "list.provider catalog right"),
+      ),
+    );
   return createHash("sha256").update(JSON.stringify(entries)).digest("hex");
 }
 
diff --git a/src/commands/onboard-inference.ts b/src/commands/onboard-inference.ts
index 3f3836f67b8a..d7168fe15bdf 100644
--- a/src/commands/onboard-inference.ts
+++ b/src/commands/onboard-inference.ts
@@ -2,6 +2,7 @@ import { randomInt } from "node:crypto";
 // Inference backend detection shared by onboarding bootstrap and Crestodian setup.
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveAgentConfig, resolveDefaultAgentId } from "../agents/agent-scope-config.js";
 import {
   readClaudeCliCredentialsCached,
@@ -120,10 +121,10 @@ function randomizeClaudeCodexTie(
   if (claudeIndex === -1 || codexIndex === -1 || pickRandomInt(2) === 0) {
     return;
   }
-  [candidates[claudeIndex], candidates[codexIndex]] = [
-    candidates[codexIndex],
-    candidates[claudeIndex],
-  ];
+  const claudeCandidate = candidates[claudeIndex];
+  const codexCandidate = candidates[codexIndex];
+  candidates[claudeIndex] = expectDefined(codexCandidate, "Codex onboarding candidate");
+  candidates[codexIndex] = expectDefined(claudeCandidate, "Claude onboarding candidate");
 }
 
 // ChatGPT.app is the current desktop owner; keep Codex stable/beta as fallbacks.
diff --git a/src/commands/onboarding-plugin-install.ts b/src/commands/onboarding-plugin-install.ts
index d6192dae4789..0e41323c5630 100644
--- a/src/commands/onboarding-plugin-install.ts
+++ b/src/commands/onboarding-plugin-install.ts
@@ -6,6 +6,7 @@
  */
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { uniqueStrings } from "@openclaw/normalization-core/string-normalization";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { sanitizeTerminalText } from "../../packages/terminal-core/src/safe-text.js";
@@ -464,7 +465,7 @@ async function promptInstallChoice(params: {
     if (realSources.length === 1) {
       // Callers that already selected a plugin/channel can skip an extra prompt
       // when there is only one viable source.
-      return realSources[0];
+      return expectDefined(realSources[0], "real sources entry at 0");
     }
   }
 
diff --git a/src/commands/sessions-cleanup.ts b/src/commands/sessions-cleanup.ts
index e493e27ed8bf..90e9772fcddf 100644
--- a/src/commands/sessions-cleanup.ts
+++ b/src/commands/sessions-cleanup.ts
@@ -304,8 +304,7 @@ export async function sessionsCleanupCommand(opts: SessionsCleanupOptions, runti
       return;
     }
 
-    for (let i = 0; i < previewResults.length; i += 1) {
-      const result = previewResults[i];
+    for (const [i, result] of previewResults.entries()) {
       if (i > 0) {
         runtime.log("");
       }
diff --git a/src/commands/status.scan-overview.ts b/src/commands/status.scan-overview.ts
index 44cbc8820a4f..660c9ad14805 100644
--- a/src/commands/status.scan-overview.ts
+++ b/src/commands/status.scan-overview.ts
@@ -238,10 +238,11 @@ export async function collectStatusScanOverview(params: {
     includeRegistryUpdate: params.includeRegistryUpdate,
     includeLocalStatusRpcFallback: params.includeLocalStatusRpcFallback,
     gatewayProbeTimeoutMs,
-    getTailnetHostname: async (runner) =>
-      await loadStatusScanDepsRuntimeModule().then(({ getTailnetHostname }) =>
+    getTailnetHostname: async (runner) => {
+      return await loadStatusScanDepsRuntimeModule().then(({ getTailnetHostname }) =>
         getTailnetHostname(runner),
-      ),
+      );
+    },
     getUpdateCheckResult: async (updateParams) =>
       await loadStatusUpdateModule().then(({ getUpdateCheckResult }) =>
         getUpdateCheckResult(updateParams),
diff --git a/src/commitments/store.ts b/src/commitments/store.ts
index d0b98e4f1916..9a21f86c7fde 100644
--- a/src/commitments/store.ts
+++ b/src/commitments/store.ts
@@ -1,6 +1,7 @@
 // Persists commitment records and claims due work for heartbeat processing.
 import { randomBytes } from "node:crypto";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isRecord } from "@openclaw/normalization-core/record-coerce";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import type { OpenClawConfig } from "../config/config.js";
@@ -390,7 +391,10 @@ export async function upsertInferredCommitments(params: {
           isActiveStatus(commitment.status),
       );
       if (existingIndex >= 0) {
-        const existing = store.commitments[existingIndex];
+        const existing = expectDefined(
+          store.commitments[existingIndex],
+          "commitments entry at existing index",
+        );
         store.commitments[existingIndex] = {
           ...existing,
           reason: entry.candidate.reason.trim() || existing.reason,
diff --git a/src/config/config-paths.ts b/src/config/config-paths.ts
index 6037dde34bd8..5fcd5a7bb0a9 100644
--- a/src/config/config-paths.ts
+++ b/src/config/config-paths.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 import { isBlockedObjectKey } from "../infra/prototype-keys.js";
 // Resolves and classifies config paths for reads, writes, and metadata.
 import { isPlainObject } from "../utils.js";
@@ -47,9 +48,12 @@ export function parseConfigPath(raw: string): {
 
 /** Sets a value at a validated config path, creating missing plain-object parents. */
 export function setConfigValueAtPath(root: PathNode, path: string[], value: unknown): void {
+  const leafKey = path.at(-1);
+  if (leafKey === undefined) {
+    throw new Error("Config path must contain at least one segment");
+  }
   let cursor: PathNode = root;
-  for (let idx = 0; idx < path.length - 1; idx += 1) {
-    const key = path[idx];
+  for (const key of path.slice(0, -1)) {
     const existing = Object.hasOwn(cursor, key) ? cursor[key] : undefined;
     const next: PathNode = isPlainObject(existing) ? existing : {};
     if (next !== existing) {
@@ -57,15 +61,18 @@ export function setConfigValueAtPath(root: PathNode, path: string[], value: unkn
     }
     cursor = next;
   }
-  setOwnConfigProperty(cursor, path[path.length - 1], value);
+  setOwnConfigProperty(cursor, leafKey, value);
 }
 
 /** Removes a value at a config path and prunes empty parent objects created by setters. */
 export function unsetConfigValueAtPath(root: PathNode, path: string[]): boolean {
+  const leafKey = path.at(-1);
+  if (leafKey === undefined) {
+    return false;
+  }
   const stack: Array<{ node: PathNode; key: string }> = [];
   let cursor: PathNode = root;
-  for (let idx = 0; idx < path.length - 1; idx += 1) {
-    const key = path[idx];
+  for (const key of path.slice(0, -1)) {
     if (!Object.hasOwn(cursor, key)) {
       return false;
     }
@@ -76,7 +83,6 @@ export function unsetConfigValueAtPath(root: PathNode, path: string[]): boolean
     stack.push({ node: cursor, key });
     cursor = next;
   }
-  const leafKey = path[path.length - 1];
   if (!Object.hasOwn(cursor, leafKey)) {
     return false;
   }
@@ -84,7 +90,7 @@ export function unsetConfigValueAtPath(root: PathNode, path: string[]): boolean
   // Keep config writes tidy: removing foo.bar should also remove foo when it became empty, while
   // preserving any parent that still carries sibling config.
   for (let idx = stack.length - 1; idx >= 0; idx -= 1) {
-    const { node, key } = stack[idx];
+    const { node, key } = expectDefined(stack[idx], "stack entry at idx");
     const child = node[key];
     if (isPlainObject(child) && Object.keys(child).length === 0) {
       delete node[key];
diff --git a/src/config/env-preserve.ts b/src/config/env-preserve.ts
index 463ca0a923fb..d3778585ab17 100644
--- a/src/config/env-preserve.ts
+++ b/src/config/env-preserve.ts
@@ -1,5 +1,6 @@
 // Normalizes preserved environment-variable config for subprocess launches.
 import { isDeepStrictEqual } from "node:util";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isPlainObject } from "../infra/plain-object.js";
 
 /**
@@ -615,7 +616,7 @@ function matchAuthoredEscapedTemplateArrayItems(params: {
       const sameIndexMatch = incomingMatches.includes(parsedIndex)
         ? parsedIndex
         : incomingMatches[0];
-      addMatch(parsedIndex, sameIndexMatch);
+      addMatch(parsedIndex, expectDefined(sameIndexMatch, "env preserve same index match"));
       continue;
     }
     if (incomingMatches.length > 0) {
@@ -696,7 +697,7 @@ function tryResolveString(template: string, env: NodeJS.ProcessEnv): string {
         }
       }
     }
-    chunks.push(template[i]);
+    chunks.push(template.charAt(i));
   }
 
   return chunks.join("");
diff --git a/src/config/env-substitution.ts b/src/config/env-substitution.ts
index 37f57dd77d1a..942830b7b65c 100644
--- a/src/config/env-substitution.ts
+++ b/src/config/env-substitution.ts
@@ -101,7 +101,7 @@ function substituteString(
   const chunks: string[] = [];
 
   for (let i = 0; i < value.length; i += 1) {
-    const char = value[i];
+    const char = value.charAt(i);
     if (char !== "$") {
       chunks.push(char);
       continue;
diff --git a/src/config/includes.ts b/src/config/includes.ts
index ee6aa87eeebf..42da321f066f 100644
--- a/src/config/includes.ts
+++ b/src/config/includes.ts
@@ -13,6 +13,7 @@
 import crypto from "node:crypto";
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { canUseRootFileOpen, openRootFileSync } from "../infra/boundary-file-read.js";
 import { resolvePathViaExistingAncestorSync } from "../infra/boundary-path.js";
 import { isBlockedObjectKey } from "../infra/prototype-keys.js";
@@ -122,7 +123,10 @@ export class ConfigIncludeError extends Error {
 
 export class CircularIncludeError extends ConfigIncludeError {
   constructor(public readonly chain: string[]) {
-    super(`Circular include detected: ${chain.join(" -> ")}`, chain[chain.length - 1]);
+    super(
+      `Circular include detected: ${chain.join(" -> ")}`,
+      expectDefined(chain[chain.length - 1], "chain entry at chain.length 1"),
+    );
     this.name = "CircularIncludeError";
   }
 }
diff --git a/src/config/io.write-prepare.ts b/src/config/io.write-prepare.ts
index 39cfbae35ac4..8a8b378d045c 100644
--- a/src/config/io.write-prepare.ts
+++ b/src/config/io.write-prepare.ts
@@ -1,6 +1,7 @@
 // Prepares config writes by diffing current state and preserving metadata.
 import { isDeepStrictEqual } from "node:util";
 import { normalizeConfiguredProviderCatalogModelId } from "@openclaw/model-catalog-core/provider-model-id-normalization";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isBlockedObjectKey } from "../infra/prototype-keys.js";
 import { parseConfigPathArrayIndex } from "../shared/path-array-index.js";
 import { isRecord } from "../utils.js";
@@ -215,7 +216,8 @@ function setPathValue(value: unknown, path: string[], nextValue: unknown): unkno
   if (path.length === 0) {
     return cloneUnknown(nextValue);
   }
-  const [head, ...tail] = path;
+  const head = expectDefined(path[0], "config path head");
+  const tail = path.slice(1);
   if (Array.isArray(value)) {
     const index = parseArrayIndexPathSegment(head);
     if (index === undefined || index >= value.length) {
@@ -273,7 +275,8 @@ function setPathValueCreatingParents(value: unknown, path: string[], nextValue:
   if (path.length === 0) {
     return cloneUnknown(nextValue);
   }
-  const [head, ...tail] = path;
+  const head = expectDefined(path[0], "config path head");
+  const tail = path.slice(1);
   if (Array.isArray(value) || isNumericPathSegment(head)) {
     const index = parseArrayIndexPathSegment(head);
     if (index === undefined) {
@@ -294,7 +297,8 @@ function deletePathValue(value: unknown, path: string[]): unknown {
   if (path.length === 0) {
     return value;
   }
-  const [head, ...tail] = path;
+  const head = expectDefined(path[0], "config path head");
+  const tail = path.slice(1);
   if (Array.isArray(value)) {
     const index = parseArrayIndexPathSegment(head);
     if (index === undefined || index >= value.length || tail.length === 0) {
@@ -786,7 +790,8 @@ function hasPathValue(value: unknown, path: readonly string[]): boolean {
   if (path.length === 0) {
     return true;
   }
-  const [head, ...tail] = path;
+  const head = expectDefined(path[0], "config path head");
+  const tail = path.slice(1);
   if (Array.isArray(value)) {
     const index = parseArrayIndexPathSegment(head);
     if (index === undefined || index >= value.length) {
@@ -1019,7 +1024,7 @@ function unsetPathForWriteAt(
   if (depth >= pathSegments.length) {
     return { changed: false, value };
   }
-  const segment = pathSegments[depth];
+  const segment = expectDefined(pathSegments[depth], "path segments entry at depth");
   const isLeaf = depth === pathSegments.length - 1;
 
   if (Array.isArray(value)) {
diff --git a/src/config/mcp-config.ts b/src/config/mcp-config.ts
index 78f9db818ef5..f64a1a007e25 100644
--- a/src/config/mcp-config.ts
+++ b/src/config/mcp-config.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Normalizes MCP server config for runtime launch and validation.
 import { isRecord } from "../utils.js";
 import { readSourceConfigSnapshot } from "./io.js";
@@ -157,7 +158,7 @@ async function updateConfiguredMcpServerConfig(params: {
 
   const validated = validateConfigObjectWithPlugins(next);
   if (!validated.ok) {
-    const issue = validated.issues[0];
+    const issue = expectDefined(validated.issues[0], "issues entry at 0");
     return {
       ok: false,
       path: loaded.path,
@@ -276,7 +277,7 @@ export async function setConfiguredMcpServer(params: {
 
   const validated = validateConfigObjectWithPlugins(next);
   if (!validated.ok) {
-    const issue = validated.issues[0];
+    const issue = expectDefined(validated.issues[0], "issues entry at 0");
     return {
       ok: false,
       path: loaded.path,
@@ -334,7 +335,7 @@ export async function unsetConfiguredMcpServer(params: {
 
   const validated = validateConfigObjectWithPlugins(next);
   if (!validated.ok) {
-    const issue = validated.issues[0];
+    const issue = expectDefined(validated.issues[0], "issues entry at 0");
     return {
       ok: false,
       path: loaded.path,
diff --git a/src/config/mutate.ts b/src/config/mutate.ts
index c2a842975b6a..6957e16ea2b1 100644
--- a/src/config/mutate.ts
+++ b/src/config/mutate.ts
@@ -3,6 +3,7 @@ import { AsyncLocalStorage } from "node:async_hooks";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { isDeepStrictEqual } from "node:util";
+import { expectDefined } from "@openclaw/normalization-core";
 import { KeyedAsyncQueue } from "openclaw/plugin-sdk/keyed-async-queue";
 import { formatErrorMessage } from "../infra/errors.js";
 import { withFileLock } from "../infra/file-lock.js";
@@ -577,7 +578,7 @@ async function tryWriteSingleTopLevelIncludeMutation(params: {
     return null;
   }
 
-  const key = changedKeys[0];
+  const key = expectDefined(changedKeys[0], "changed keys entry at 0");
   const includePath = getSingleTopLevelIncludeTarget({ snapshot: params.snapshot, key });
   if (!includePath || !isRecord(nextConfig) || !(key in nextConfig)) {
     return null;
diff --git a/src/config/plugin-auto-enable.prefer-over.ts b/src/config/plugin-auto-enable.prefer-over.ts
index 9a69760cfdcf..fe74d8f733ac 100644
--- a/src/config/plugin-auto-enable.prefer-over.ts
+++ b/src/config/plugin-auto-enable.prefer-over.ts
@@ -3,7 +3,7 @@ import fs from "node:fs";
 import path from "node:path";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { normalizeStringEntries } from "@openclaw/normalization-core/string-normalization";
-import { getChatChannelMeta, normalizeChatChannelId } from "../channels/registry.js";
+import { findChatChannelMeta, normalizeChatChannelId } from "../channels/registry.js";
 import type { PluginManifestRegistry } from "../plugins/manifest-registry.js";
 import { isRecord, resolveConfigDir, resolveUserPath } from "../utils.js";
 import type { PluginAutoEnableCandidate } from "./plugin-auto-enable.types.js";
@@ -97,7 +97,7 @@ function resolveBuiltInChannelPreferOver(channelId: string): readonly string[] {
   if (!builtInChannelId) {
     return [];
   }
-  return getChatChannelMeta(builtInChannelId)?.preferOver ?? [];
+  return findChatChannelMeta(builtInChannelId)?.preferOver ?? [];
 }
 
 function resolvePreferredOverIds(
diff --git a/src/config/plugin-auto-enable.shared.ts b/src/config/plugin-auto-enable.shared.ts
index 7fcf9cfff14d..58a12e76ac67 100644
--- a/src/config/plugin-auto-enable.shared.ts
+++ b/src/config/plugin-auto-enable.shared.ts
@@ -1,6 +1,7 @@
 // Shares plugin auto-enable detection across config and runtime code.
 import { collectConfiguredModelRefs } from "@openclaw/model-catalog-core/configured-model-refs";
 import { normalizeProviderId } from "@openclaw/model-catalog-core/provider-id";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
 import { collectConfiguredAgentHarnessRuntimes } from "../agents/harness-runtimes.js";
 import {
@@ -11,7 +12,7 @@ import {
   hasBundledChannelConfiguredState,
   listBundledChannelIdsWithConfiguredState,
 } from "../channels/plugins/configured-state.js";
-import { getChatChannelMeta, normalizeChatChannelId } from "../channels/registry.js";
+import { findChatChannelMeta, normalizeChatChannelId } from "../channels/registry.js";
 import { isBlockedObjectKey } from "../infra/prototype-keys.js";
 import { normalizePluginsConfig } from "../plugins/config-state.js";
 import { getCurrentPluginMetadataSnapshot } from "../plugins/current-plugin-metadata-snapshot.js";
@@ -692,7 +693,7 @@ export function resolveConfiguredPluginAutoEnableCandidates(params: {
     });
     if (owningPluginIds?.length === 1) {
       changes.push({
-        pluginId: owningPluginIds[0],
+        pluginId: expectDefined(owningPluginIds[0], "owning plugin ids entry at 0"),
         kind: "provider-model-configured",
         modelRef,
       });
@@ -1013,7 +1014,7 @@ function resolveChannelAutoEnableDisplayLabel(
   const builtInChannelId = normalizeChatChannelId(entry.channelId);
   const plugin = manifestRegistry.plugins.find((record) => record.id === entry.pluginId);
   return (
-    (builtInChannelId ? getChatChannelMeta(builtInChannelId)?.label : undefined) ??
+    (builtInChannelId ? findChatChannelMeta(builtInChannelId)?.label : undefined) ??
     plugin?.channelConfigs?.[entry.channelId]?.label ??
     plugin?.channelCatalogMeta?.label
   );
diff --git a/src/config/sessions/combined-store-gateway.ts b/src/config/sessions/combined-store-gateway.ts
index 56b314b3801b..884f0fd5834e 100644
--- a/src/config/sessions/combined-store-gateway.ts
+++ b/src/config/sessions/combined-store-gateway.ts
@@ -1,6 +1,7 @@
 // Builds the gateway-visible combined session store across agent-specific stores.
 // Gateway callers need canonical per-agent keys even when stores are split by `{agentId}`.
 
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveDefaultAgentId } from "../../agents/agent-scope.js";
 import {
   canonicalizeSpawnedByForAgent,
@@ -140,7 +141,7 @@ export function loadCombinedSessionStoreForGateway(
 
   const storePath =
     targets.length === 1
-      ? targets[0].storePath
+      ? expectDefined(targets[0], "targets entry at 0").storePath
       : typeof storeConfig === "string" && storeConfig.trim()
         ? storeConfig.trim()
         : "(multiple)";
diff --git a/src/config/sessions/session-accessor.sqlite.ts b/src/config/sessions/session-accessor.sqlite.ts
index ca1cb43ba1c6..d9e178169fa9 100644
--- a/src/config/sessions/session-accessor.sqlite.ts
+++ b/src/config/sessions/session-accessor.sqlite.ts
@@ -1299,6 +1299,9 @@ export async function purgeSqliteDeletedAgentSessionEntries(
         continue;
       }
       const entry = store[sessionKey];
+      if (!entry) {
+        continue;
+      }
       entryRemovals.push({ expectedEntry: cloneSessionEntry(entry), sessionKey });
       removedEntriesToArchive.push(entry);
       delete remainingStore[sessionKey];
diff --git a/src/config/sessions/store-cache.ts b/src/config/sessions/store-cache.ts
index cfe8821fbec5..67cb3cfa937c 100644
--- a/src/config/sessions/store-cache.ts
+++ b/src/config/sessions/store-cache.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Session store caches share parsed stores, immutable snapshots, and serialized JSON.
 import { parseStrictNonNegativeInteger } from "../../infra/parse-finite-number.js";
 import { createExpiringMapCache, isCacheEnabled, resolveCacheTtlMs } from "../cache-utils.js";
@@ -249,7 +250,9 @@ export function cloneSessionStoreSnapshot(
 }
 
 export function cloneSessionStoreSnapshotEntry(entry: SessionEntry): SessionStoreSnapshotEntry {
-  return deepFreeze(cloneSessionStoreRecord({ entry }).entry);
+  return deepFreeze(
+    expectDefined(cloneSessionStoreRecord({ entry }).entry, "cloned session cache entry"),
+  );
 }
 
 function getSessionStoreTtl(): number {
diff --git a/src/config/sessions/store.ts b/src/config/sessions/store.ts
index 8b15e6b4c0dc..ca19565a71ab 100644
--- a/src/config/sessions/store.ts
+++ b/src/config/sessions/store.ts
@@ -1,6 +1,7 @@
 // Session store facade coordinates reads, writes, maintenance, delivery metadata, and exports.
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { normalizeOptionalAgentRuntimeId } from "../../agents/agent-runtime-id.js";
 import type { MsgContext } from "../../auto-reply/templating.js";
@@ -343,7 +344,7 @@ export type DeletedAgentSessionEntryPurgeParams = {
 };
 
 function cloneSessionEntry(entry: SessionEntry): SessionEntry {
-  return cloneSessionStoreRecord({ entry }).entry;
+  return expectDefined(cloneSessionStoreRecord({ entry }).entry, "cloned session entry");
 }
 
 function cloneSessionEntries(store: Record<string, SessionEntry>): Record<string, SessionEntry> {
@@ -1292,7 +1293,11 @@ export async function applySessionEntryPatchProjection<
       ...target,
       entries: cloneSessionEntryProjectionSnapshot(store).entries,
       ...(store[target.primaryKey]
-        ? { existingEntry: cloneSessionEntry(store[target.primaryKey]) }
+        ? {
+            existingEntry: cloneSessionEntry(
+              expectDefined(store[target.primaryKey], "store entry at target.primary key"),
+            ),
+          }
         : {}),
     });
     if (projected.ok) {
diff --git a/src/config/types.secrets.ts b/src/config/types.secrets.ts
index b723f0c871e7..e5989ce0ce7d 100644
--- a/src/config/types.secrets.ts
+++ b/src/config/types.secrets.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Defines secret reference and resolution configuration types.
 import { isRecord } from "../utils.js";
 
@@ -97,7 +98,7 @@ export function parseEnvTemplateSecretRef(
   return {
     source: "env",
     provider: provider.trim() || DEFAULT_SECRET_PROVIDER_ALIAS,
-    id: match[1],
+    id: expectDefined(match[1], "types.secrets regex capture 1"),
   };
 }
 
diff --git a/src/config/validation.ts b/src/config/validation.ts
index 8857c9ef3251..84855baee7a1 100644
--- a/src/config/validation.ts
+++ b/src/config/validation.ts
@@ -783,7 +783,9 @@ function filterUnsupportedMutableSecretRefSchemaIssue(params: {
   if (!unrecognizedKeys.includes(childKey)) {
     return issue;
   }
-  const remainingKeys = unrecognizedKeys.filter((key) => key !== childKey);
+  const remainingKeys = unrecognizedKeys.filter(
+    (key): key is string => key !== undefined && key !== childKey,
+  );
   if (remainingKeys.length === 0) {
     return null;
   }
diff --git a/src/config/version.ts b/src/config/version.ts
index e1a3e324439e..580267b53717 100644
--- a/src/config/version.ts
+++ b/src/config/version.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Normalizes config version metadata and compatibility comparisons.
 import {
   comparePrereleaseIdentifiers,
@@ -27,9 +28,9 @@ export function parseOpenClawVersion(raw: string | null | undefined): OpenClawVe
   const [, major, minor, patch, suffix] = match;
   const revision = suffix && /^[0-9]+$/.test(suffix) ? Number.parseInt(suffix, 10) : null;
   return {
-    major: Number.parseInt(major, 10),
-    minor: Number.parseInt(minor, 10),
-    patch: Number.parseInt(patch, 10),
+    major: Number.parseInt(expectDefined(major, "version major"), 10),
+    minor: Number.parseInt(expectDefined(minor, "version minor"), 10),
+    patch: Number.parseInt(expectDefined(patch, "version patch"), 10),
     revision,
     prerelease: suffix && revision == null ? suffix.split(".").filter(Boolean) : null,
   };
diff --git a/src/config/zod-schema.ts b/src/config/zod-schema.ts
index 2ab136c18f9a..23335b27eb57 100644
--- a/src/config/zod-schema.ts
+++ b/src/config/zod-schema.ts
@@ -1612,8 +1612,7 @@ export const OpenClawSchema = z
       if (!Array.isArray(ids)) {
         continue;
       }
-      for (let idx = 0; idx < ids.length; idx += 1) {
-        const agentId = ids[idx];
+      for (const [idx, agentId] of ids.entries()) {
         if (!agentIds.has(agentId)) {
           ctx.addIssue({
             code: z.ZodIssueCode.custom,
diff --git a/src/crestodian/setup-inference.ts b/src/crestodian/setup-inference.ts
index a50cd04b642a..d4ba78050771 100644
--- a/src/crestodian/setup-inference.ts
+++ b/src/crestodian/setup-inference.ts
@@ -4,6 +4,7 @@ import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
 import { isDeepStrictEqual } from "node:util";
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveAgentEffectiveModelPrimary, resolveDefaultAgentId } from "../agents/agent-scope.js";
 import { normalizeAuthProfileCredential } from "../agents/auth-profiles/credential-normalize.js";
 import { loadPersistedAuthProfileStore } from "../agents/auth-profiles/persisted.js";
@@ -708,7 +709,12 @@ function copySelectedModelMetadata(params: {
         ...params.target.agents?.defaults,
         models: {
           ...params.target.agents?.defaults?.models,
-          [params.modelRef]: structuredClone(preparedDefaultModels[params.modelRef]),
+          [params.modelRef]: structuredClone(
+            expectDefined(
+              preparedDefaultModels[params.modelRef],
+              "prepared default models entry at params.model ref",
+            ),
+          ),
         },
       },
     };
@@ -725,13 +731,18 @@ function copySelectedModelMetadata(params: {
     return;
   }
   const nextAgents = structuredClone(targetAgents);
-  const targetAgent = nextAgents[targetAgentIndex];
+  const targetAgent = expectDefined(
+    nextAgents[targetAgentIndex],
+    "next agents entry at target agent index",
+  );
   if (!targetAgent) {
     return;
   }
   targetAgent.models = {
     ...targetAgent.models,
-    [params.modelRef]: structuredClone(preparedAgent.models[params.modelRef]),
+    [params.modelRef]: structuredClone(
+      expectDefined(preparedAgent.models[params.modelRef], "models entry at params.model ref"),
+    ),
   };
   params.target.agents = { ...params.target.agents, list: nextAgents };
 }
@@ -782,13 +793,15 @@ function projectManualInferenceConfig(params: {
 
   const providerConfigKey = findSelectedProviderConfigKey(params.preparedConfig, params.providerId);
   if (providerConfigKey) {
+    const preparedProvider = params.preparedConfig.models?.providers?.[providerConfigKey];
+    if (preparedProvider === undefined) {
+      throw new Error(`Prepared provider config missing for ${providerConfigKey}`);
+    }
     config.models = {
       ...config.models,
       providers: {
         ...config.models?.providers,
-        [providerConfigKey]: structuredClone(
-          params.preparedConfig.models!.providers![providerConfigKey],
-        ),
+        [providerConfigKey]: structuredClone(preparedProvider),
       },
     };
   }
diff --git a/src/cron/isolated-agent.test-setup.ts b/src/cron/isolated-agent.test-setup.ts
index 75915125719e..59cd73f9bdde 100644
--- a/src/cron/isolated-agent.test-setup.ts
+++ b/src/cron/isolated-agent.test-setup.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Isolated agent test setup centralizes common mocks for cron agent tests.
 import { vi } from "vitest";
 import { runEmbeddedAgent } from "../agents/embedded-agent.js";
@@ -46,24 +47,35 @@ function parseTelegramTargetForTest(raw: string): {
   const match = /^group:([^:]+):topic:(\d+)$/i.exec(trimmed);
   if (match) {
     return {
-      chatId: match[1],
-      messageThreadId: Number.parseInt(match[2], 10),
+      chatId: expectDefined(match[1], "isolated agent.test setup regex capture 1"),
+      messageThreadId: Number.parseInt(
+        expectDefined(match[2], "isolated agent.test setup regex capture 2"),
+        10,
+      ),
       chatType: "group",
     };
   }
   const topicMatch = /^([^:]+):topic:(\d+)$/i.exec(trimmed);
   if (topicMatch) {
     return {
-      chatId: topicMatch[1],
-      messageThreadId: Number.parseInt(topicMatch[2], 10),
-      chatType: topicMatch[1].startsWith("-") ? "group" : "direct",
+      chatId: expectDefined(topicMatch[1], "topic match capture group 1"),
+      messageThreadId: Number.parseInt(
+        expectDefined(topicMatch[2], "topic match capture group 2"),
+        10,
+      ),
+      chatType: expectDefined(topicMatch[1], "topic match capture group 1").startsWith("-")
+        ? "group"
+        : "direct",
     };
   }
   const colonPair = /^([^:]+):(\d+)$/i.exec(trimmed);
-  if (colonPair && colonPair[1].startsWith("-")) {
+  if (colonPair && expectDefined(colonPair[1], "colon pair capture group 1").startsWith("-")) {
     return {
-      chatId: colonPair[1],
-      messageThreadId: Number.parseInt(colonPair[2], 10),
+      chatId: expectDefined(colonPair[1], "colon pair capture group 1"),
+      messageThreadId: Number.parseInt(
+        expectDefined(colonPair[2], "colon pair capture group 2"),
+        10,
+      ),
       chatType: "group",
     };
   }
diff --git a/src/cron/isolated-agent/model-preflight.runtime.ts b/src/cron/isolated-agent/model-preflight.runtime.ts
index 18c6cb70f653..b4d5c7b36263 100644
--- a/src/cron/isolated-agent/model-preflight.runtime.ts
+++ b/src/cron/isolated-agent/model-preflight.runtime.ts
@@ -1,5 +1,6 @@
 /** Preflights local model-provider endpoints before scheduled cron runner startup. */
 import { normalizeProviderId } from "@openclaw/model-catalog-core/provider-id";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import type { ModelProviderConfig } from "../../config/types.models.js";
 import type { OpenClawConfig } from "../../config/types.openclaw.js";
@@ -75,7 +76,13 @@ function isPrivateIpv4Host(host: string): boolean {
     return false;
   }
   const [a, b] = octets;
-  return a === 10 || (a === 172 && b >= 16 && b <= 31) || (a === 192 && b === 168);
+  return (
+    a === 10 ||
+    (a === 172 &&
+      expectDefined(b, "model preflight.runtime b") >= 16 &&
+      expectDefined(b, "model preflight.runtime b") <= 31) ||
+    (a === 192 && b === 168)
+  );
 }
 
 function isLocalProviderBaseUrl(baseUrl: string): boolean {
diff --git a/src/cron/service/jobs.ts b/src/cron/service/jobs.ts
index 24bdf3d0363b..9bc4e5a9343f 100644
--- a/src/cron/service/jobs.ts
+++ b/src/cron/service/jobs.ts
@@ -1,5 +1,6 @@
 /** Cron job scheduling, validation, creation, and patch helpers. */
 import crypto from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeOptionalString,
   normalizeOptionalThreadValue,
@@ -76,7 +77,10 @@ export function errorBackoffMs(
   scheduleMs = DEFAULT_ERROR_BACKOFF_SCHEDULE_MS,
 ): number {
   const idx = Math.min(consecutiveErrors - 1, scheduleMs.length - 1);
-  return scheduleMs[Math.max(0, idx)] ?? DEFAULT_ERROR_BACKOFF_SCHEDULE_MS[0];
+  return (
+    expectDefined(scheduleMs[Math.max(0, idx)], "schedule ms entry at math.max(0, idx)") ??
+    DEFAULT_ERROR_BACKOFF_SCHEDULE_MS[0]
+  );
 }
 
 /** Returns the earliest retry timestamp after a failed cron run and its runtime duration. */
diff --git a/src/cron/stagger.ts b/src/cron/stagger.ts
index 31c20e574698..720434b2b144 100644
--- a/src/cron/stagger.ts
+++ b/src/cron/stagger.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Resolves deterministic cron stagger windows for recurring schedules. */
 import { parseStrictNonNegativeInteger } from "../infra/parse-finite-number.js";
 import type { CronSchedule } from "./types.js";
@@ -24,11 +25,18 @@ export function isRecurringTopOfHourCronExpr(expr: string) {
   const fields = parseCronFields(expr);
   if (fields.length === 5) {
     const [minuteField, hourField] = fields;
-    return minuteField === "0" && hasRecurringWildcardHour(hourField);
+    return (
+      minuteField === "0" &&
+      hasRecurringWildcardHour(expectDefined(hourField, "stagger hour field"))
+    );
   }
   if (fields.length === 6) {
     const [secondField, minuteField, hourField] = fields;
-    return secondField === "0" && minuteField === "0" && hasRecurringWildcardHour(hourField);
+    return (
+      secondField === "0" &&
+      minuteField === "0" &&
+      hasRecurringWildcardHour(expectDefined(hourField, "stagger hour field"))
+    );
   }
   return false;
 }
diff --git a/src/daemon/arg-split.ts b/src/daemon/arg-split.ts
index 91e821756b08..56f62876ab50 100644
--- a/src/daemon/arg-split.ts
+++ b/src/daemon/arg-split.ts
@@ -20,7 +20,7 @@ export function splitArgsPreservingQuotes(
   const quoteStart = options?.quoteStart ?? "anywhere";
 
   for (let i = 0; i < value.length; i++) {
-    const char = value[i];
+    const char = value.charAt(i);
     if (escapeMode === "backslash" && char === "\\") {
       // POSIX-style service parsers consume any escaped next byte.
       if (i + 1 < value.length) {
diff --git a/src/daemon/launchd-plist.ts b/src/daemon/launchd-plist.ts
index 0984e7b31ad1..68dea087f441 100644
--- a/src/daemon/launchd-plist.ts
+++ b/src/daemon/launchd-plist.ts
@@ -236,24 +236,44 @@ export async function readLaunchAgentProgramArgumentsFromFile(
     if (!programMatch) {
       return null;
     }
-    const args = Array.from(programMatch[1].matchAll(/<string>([\s\S]*?)<\/string>/gi)).map(
-      (match) => plistUnescape(match[1] ?? "").trim(),
-    );
+    const programArgumentsXml = programMatch.at(1);
+    if (programArgumentsXml === undefined) {
+      return null;
+    }
+    const args: string[] = [];
+    for (const match of programArgumentsXml.matchAll(/<string>([\s\S]*?)<\/string>/gi)) {
+      const rawArgument = match.at(1);
+      if (rawArgument === undefined) {
+        return null;
+      }
+      args.push(plistUnescape(rawArgument).trim());
+    }
     const workingDirMatch = plist.match(
       /<key>WorkingDirectory<\/key>\s*<string>([\s\S]*?)<\/string>/i,
     );
-    const workingDirectory = workingDirMatch ? plistUnescape(workingDirMatch[1] ?? "").trim() : "";
+    const workingDirectoryXml = workingDirMatch?.at(1);
+    const workingDirectory =
+      workingDirectoryXml === undefined ? "" : plistUnescape(workingDirectoryXml).trim();
     const envMatch = plist.match(/<key>EnvironmentVariables<\/key>\s*<dict>([\s\S]*?)<\/dict>/i);
     const inlineEnvironment: Record<string, string> = {};
     if (envMatch) {
-      for (const pair of envMatch[1].matchAll(
+      const environmentXml = envMatch.at(1);
+      if (environmentXml === undefined) {
+        return null;
+      }
+      for (const pair of environmentXml.matchAll(
         /<key>([\s\S]*?)<\/key>\s*<string>([\s\S]*?)<\/string>/gi,
       )) {
-        const key = plistUnescape(pair[1] ?? "").trim();
+        const rawKey = pair.at(1);
+        const rawValue = pair.at(2);
+        if (rawKey === undefined || rawValue === undefined) {
+          return null;
+        }
+        const key = plistUnescape(rawKey).trim();
         if (!key) {
           continue;
         }
-        const value = plistUnescape(pair[2] ?? "").trim();
+        const value = plistUnescape(rawValue).trim();
         inlineEnvironment[key] = value;
       }
     }
diff --git a/src/daemon/schtasks.ts b/src/daemon/schtasks.ts
index 849447fd5b75..13af56dbd262 100644
--- a/src/daemon/schtasks.ts
+++ b/src/daemon/schtasks.ts
@@ -3,6 +3,7 @@ import { spawn, spawnSync } from "node:child_process";
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { uniqueStrings } from "@openclaw/normalization-core/string-normalization";
 import { isGatewayArgv } from "../infra/gateway-process-argv.js";
@@ -526,7 +527,7 @@ async function launchFallbackTaskScript(
     installedCommand === undefined ? await readScheduledTaskCommand(env) : installedCommand;
   if (command?.programArguments.length) {
     const [executable, ...args] = command.programArguments;
-    const child = spawn(executable, args, {
+    const child = spawn(expectDefined(executable, "schtasks executable"), args, {
       cwd: command.workingDirectory || undefined,
       detached: true,
       env: {
diff --git a/src/daemon/service-audit.ts b/src/daemon/service-audit.ts
index 222fb61a4af2..cfd76c1430f5 100644
--- a/src/daemon/service-audit.ts
+++ b/src/daemon/service-audit.ts
@@ -299,8 +299,7 @@ function readGatewayServiceCommandPortState(
   if (!programArguments || programArguments.length === 0) {
     return { kind: "missing" };
   }
-  for (let index = 0; index < programArguments.length; index += 1) {
-    const arg = programArguments[index];
+  for (const [index, arg] of programArguments.entries()) {
     if (arg === "--port") {
       return parseGatewayPortArg(programArguments[index + 1]);
     }
diff --git a/src/entry.compile-cache.ts b/src/entry.compile-cache.ts
index 6d383dc1c7a5..c2211143cd0e 100644
--- a/src/entry.compile-cache.ts
+++ b/src/entry.compile-cache.ts
@@ -5,6 +5,7 @@ import { enableCompileCache, getCompileCacheDir } from "node:module";
 import os from "node:os";
 import path from "node:path";
 import process from "node:process";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isTerminalInteractiveRespawnArgv } from "./cli/respawn-policy.js";
 import { attachChildProcessBridge } from "./process/child-process-bridge.js";
 import {
@@ -48,8 +49,8 @@ export function isNodeVersionAffectedByCompileCacheDeadlock(
   if (!match) {
     return false;
   }
-  const major = Number.parseInt(match[1], 10);
-  const minor = Number.parseInt(match[2], 10);
+  const major = Number.parseInt(expectDefined(match[1], "compile-cache major version capture"), 10);
+  const minor = Number.parseInt(expectDefined(match[2], "compile-cache minor version capture"), 10);
   if (major !== 24) {
     return false;
   }
diff --git a/src/flows/provider-flow.runtime.ts b/src/flows/provider-flow.runtime.ts
index 2d4dd6d664dc..649e7c29dcd4 100644
--- a/src/flows/provider-flow.runtime.ts
+++ b/src/flows/provider-flow.runtime.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Provider flow runtime helpers load provider setup behavior behind runtime imports.
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
@@ -60,8 +61,12 @@ export function resolveProviderModelPickerFlowContributions(params?: {
   return sortFlowContributionsByLabel(
     providerWizard.resolveProviderModelPickerEntries(params ?? {}).map((entry) => {
       const providerId = entry.value.startsWith("provider-plugin:")
-        ? entry.value.slice("provider-plugin:".length).split(":")[0]
+        ? expectDefined(
+            entry.value.slice("provider-plugin:".length).split(":").at(0),
+            "provider id",
+          )
         : entry.value;
+      const docsPath = docsByProvider.get(providerId);
       // Provider-plugin values encode plugin/provider in the option value; docs attach by provider id.
       return {
         id: `provider:model-picker:${entry.value}`,
@@ -72,9 +77,7 @@ export function resolveProviderModelPickerFlowContributions(params?: {
           value: entry.value,
           label: entry.label,
           ...(entry.hint ? { hint: entry.hint } : {}),
-          ...(docsByProvider.get(providerId)
-            ? { docs: { path: docsByProvider.get(providerId)! } }
-            : {}),
+          ...(docsPath ? { docs: { path: docsPath } } : {}),
         },
         source: "runtime" as const,
       };
diff --git a/src/gateway/chat-attachments.ts b/src/gateway/chat-attachments.ts
index 45c6d8fd87e6..62fe39436c3d 100644
--- a/src/gateway/chat-attachments.ts
+++ b/src/gateway/chat-attachments.ts
@@ -3,6 +3,7 @@
 import { estimateBase64DecodedBytes } from "@openclaw/media-core/base64";
 import { MAX_IMAGE_BYTES } from "@openclaw/media-core/constants";
 import { extensionForMime, mimeTypeFromFilePath } from "@openclaw/media-core/mime";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
 import { formatErrorMessage } from "../infra/errors.js";
@@ -295,7 +296,7 @@ function normalizeAttachment(
   if (opts.stripDataUrlPrefix) {
     const dataUrlMatch = /^data:[^;]+;base64,(.*)$/.exec(base64);
     if (dataUrlMatch) {
-      base64 = dataUrlMatch[1];
+      base64 = expectDefined(dataUrlMatch[1], "data url match capture group 1");
     }
   }
   return { label, mime, base64 };
diff --git a/src/gateway/chat-display-projection.ts b/src/gateway/chat-display-projection.ts
index cdc2c071a4f0..3dea7e9de512 100644
--- a/src/gateway/chat-display-projection.ts
+++ b/src/gateway/chat-display-projection.ts
@@ -1,6 +1,7 @@
 // Gateway chat display projection.
 // Converts raw transcript messages into bounded Control UI/history display records.
 import { createHash } from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   asFiniteNumber,
   asPositiveSafeInteger,
@@ -1407,13 +1408,17 @@ function mergeTtsSupplementMessages(
     if (marker && isAssistantTtsSupplementMessage(message)) {
       let targetIndex = -1;
       for (let i = merged.length - 1; i >= 0; i--) {
-        if (ttsSupplementMatchesAssistant(marker, merged[i])) {
+        const candidate = merged[i];
+        if (candidate && ttsSupplementMatchesAssistant(marker, candidate)) {
           targetIndex = i;
           break;
         }
       }
       if (targetIndex >= 0) {
-        merged[targetIndex] = mergeTtsSupplementContent(merged[targetIndex], message);
+        merged[targetIndex] = mergeTtsSupplementContent(
+          expectDefined(merged[targetIndex], "merged entry at target index"),
+          message,
+        );
         changed = true;
         continue;
       }
@@ -1643,6 +1648,7 @@ function filterVisibleProjectedHistoryMessages(
     const nextRoleContent = next ? asRoleContentMessage(next) : null;
     if (
       currentRoleContent &&
+      next &&
       nextRoleContent &&
       isHeartbeatUserMessage(currentRoleContent, HEARTBEAT_PROMPT) &&
       isHeartbeatOkResponse(nextRoleContent) &&
diff --git a/src/gateway/cli-session-history.claude.ts b/src/gateway/cli-session-history.claude.ts
index edcb775db6fe..1afd04c7794b 100644
--- a/src/gateway/cli-session-history.claude.ts
+++ b/src/gateway/cli-session-history.claude.ts
@@ -191,7 +191,10 @@ function isUserToolResultMessage(message: unknown): boolean {
 function coalesceClaudeCliToolMessages(messages: TranscriptLikeMessage[]): TranscriptLikeMessage[] {
   const coalesced: TranscriptLikeMessage[] = [];
   for (let index = 0; index < messages.length; index += 1) {
-    const current = messages[index];
+    const current = messages.at(index);
+    if (current === undefined) {
+      break;
+    }
     const next = messages[index + 1];
     if (!isAssistantToolCallMessage(current) || !isUserToolResultMessage(next)) {
       coalesced.push(current);
diff --git a/src/gateway/exec-approval-manager.ts b/src/gateway/exec-approval-manager.ts
index 5417e56ce008..dbd8044d7c2a 100644
--- a/src/gateway/exec-approval-manager.ts
+++ b/src/gateway/exec-approval-manager.ts
@@ -1,6 +1,7 @@
 // Gateway exec approval manager.
 // Tracks pending operator decisions and short-lived resolved approval records.
 import { randomUUID } from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveExpiresAtMsFromDurationMs } from "@openclaw/normalization-core/number-coercion";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { buildApprovalPresentation } from "../infra/approval-presentation.js";
@@ -1086,7 +1087,10 @@ export class ExecApprovalManager<TPayload = ExecApprovalRequestPayload> {
     }
 
     if (matches.length === 1) {
-      return { kind: "prefix", id: matches[0] };
+      return {
+        kind: "prefix",
+        id: expectDefined(matches[0], "matches capture group 0"),
+      };
     }
     if (matches.length > 1) {
       return { kind: "ambiguous", ids: matches };
diff --git a/src/gateway/gateway-config-prompts.shared.ts b/src/gateway/gateway-config-prompts.shared.ts
index 3326eb2287a4..7338423080e4 100644
--- a/src/gateway/gateway-config-prompts.shared.ts
+++ b/src/gateway/gateway-config-prompts.shared.ts
@@ -1,6 +1,7 @@
 // Gateway setup prompt shared constants.
 // Provides Tailscale copy and Control UI origin updates for CLI setup flows.
 import { isIpv6Address, parseCanonicalIpAddress } from "@openclaw/net-policy/ip";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
 import { getTailnetHostname } from "../infra/tailscale.js";
@@ -75,7 +76,9 @@ export async function maybeAddTailnetOriginToControlUiAllowedOrigins(params: {
     return params.config;
   }
   const tsOrigin = await getTailnetHostname(undefined, params.tailscaleBin ?? undefined)
-    .then((host) => buildTailnetHttpsOrigin(host))
+    .then((host) =>
+      buildTailnetHttpsOrigin(expectDefined(host, "gateway config prompts.shared host")),
+    )
     .catch(() => null);
   if (!tsOrigin) {
     return params.config;
diff --git a/src/gateway/managed-image-attachments.ts b/src/gateway/managed-image-attachments.ts
index 5a7b59c55861..ab4484621b59 100644
--- a/src/gateway/managed-image-attachments.ts
+++ b/src/gateway/managed-image-attachments.ts
@@ -4,6 +4,7 @@ import { randomUUID } from "node:crypto";
 import fs from "node:fs/promises";
 import type { IncomingMessage, ServerResponse } from "node:http";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveDefaultAgentId } from "../agents/agent-scope-config.js";
 import { getRuntimeConfig } from "../config/config.js";
 import { resolveStateDir } from "../config/paths.js";
@@ -575,11 +576,17 @@ function parseManagedOutgoingRoute(value: string) {
     if (!match) {
       return null;
     }
-    if (!MANAGED_OUTGOING_ATTACHMENT_ID_RE.test(match[2])) {
+    if (
+      !MANAGED_OUTGOING_ATTACHMENT_ID_RE.test(
+        expectDefined(match[2], "managed image attachments regex capture 2"),
+      )
+    ) {
       return null;
     }
     return {
-      sessionKey: decodeURIComponent(match[1]),
+      sessionKey: decodeURIComponent(
+        expectDefined(match[1], "managed image attachments regex capture 1"),
+      ),
       attachmentId: match[2],
     };
   } catch {
@@ -607,8 +614,9 @@ function collectManagedOutgoingAttachmentRefs(
       if (expectedSessionKey && parsed.sessionKey !== expectedSessionKey) {
         continue;
       }
-      refs.set(parsed.attachmentId, {
-        attachmentId: parsed.attachmentId,
+      const attachmentId = expectDefined(parsed.attachmentId, "managed image attachment id");
+      refs.set(attachmentId, {
+        attachmentId,
         sessionKey: parsed.sessionKey,
       });
     }
diff --git a/src/gateway/node-command-policy.ts b/src/gateway/node-command-policy.ts
index f5f08f147b17..20d66baa5f4e 100644
--- a/src/gateway/node-command-policy.ts
+++ b/src/gateway/node-command-policy.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Gateway node command policy.
 // Computes per-platform allowlists from built-in, plugin, runtime, and config inputs.
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
@@ -393,7 +394,9 @@ function resolveNodeCommandAllowlistInternal(
   const platformId = normalizePlatformId(node?.platform, node?.deviceFamily);
   const base = filterDesktopHostCommandDefaults({
     platformId,
-    commands: PLATFORM_DEFAULTS[platformId] ?? PLATFORM_DEFAULTS.unknown,
+    commands:
+      expectDefined(PLATFORM_DEFAULTS[platformId], "platform defaults entry at platform id") ??
+      PLATFORM_DEFAULTS.unknown,
     includeDesktopHostCommands: options?.includeDesktopHostCommands,
   });
   const talkCommands = hasTalkSurface(node) ? TALK_PTT_COMMANDS : [];
diff --git a/src/gateway/server-methods/chat.ts b/src/gateway/server-methods/chat.ts
index 76fb5c2f714c..e2e30ec58ba5 100644
--- a/src/gateway/server-methods/chat.ts
+++ b/src/gateway/server-methods/chat.ts
@@ -5,6 +5,7 @@ import path from "node:path";
 import { performance } from "node:perf_hooks";
 import { fileURLToPath } from "node:url";
 import { isAudioFileName } from "@openclaw/media-core/mime";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isFutureDateTimestampMs } from "@openclaw/normalization-core/number-coercion";
 import { asOptionalRecord } from "@openclaw/normalization-core/record-coerce";
 import type { FastMode } from "@openclaw/normalization-core/string-coerce";
@@ -1086,7 +1087,12 @@ function replaceAssistantContentTextBlocks(
       typeof block.text === "string" &&
       transcriptTextIndex < transcriptTextBlocks.length
     ) {
-      merged.push(transcriptTextBlocks[transcriptTextIndex++]);
+      merged.push(
+        expectDefined(
+          transcriptTextBlocks[transcriptTextIndex++],
+          "transcript text blocks entry at transcript text index++",
+        ),
+      );
       continue;
     }
     merged.push(block);
@@ -1535,9 +1541,9 @@ async function prestageMediaPathOffloads(params: {
     }
 
     const stagingCtx: MsgContext = {
-      MediaPath: refsToStage[0].path,
+      MediaPath: expectDefined(refsToStage[0], "refs to stage entry at 0").path,
       MediaPaths: refsToStage.map((ref) => ref.path),
-      MediaType: refsToStage[0].mimeType,
+      MediaType: expectDefined(refsToStage[0], "refs to stage entry at 0").mimeType,
       MediaTypes: refsToStage.map((ref) => ref.mimeType),
     };
     let stageResult: StageSandboxMediaResult;
@@ -5177,7 +5183,10 @@ export const chatHandlers: GatewayRequestHandlers = {
                       runId: clientRunId,
                       sessionKey,
                       ...(sessionKey === "global" && agentId ? { agentId } : {}),
-                      question: btwReplies[0].btw.question.trim(),
+                      question: expectDefined(
+                        btwReplies[0],
+                        "btw replies entry at 0",
+                      ).btw.question.trim(),
                       text: btwText,
                       isError: btwReplies.some((payload) => payload.isError),
                       ts: Date.now(),
diff --git a/src/gateway/server-methods/doctor.ts b/src/gateway/server-methods/doctor.ts
index 252febbaeb42..ea7dd6f5d21c 100644
--- a/src/gateway/server-methods/doctor.ts
+++ b/src/gateway/server-methods/doctor.ts
@@ -2,6 +2,7 @@
 // cron state, and REM harness previews for operator diagnostics.
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { asOptionalRecord } from "@openclaw/normalization-core/record-coerce";
 import { resolveAgentWorkspaceDir, resolveDefaultAgentId } from "../../agents/agent-scope.js";
 import type { OpenClawConfig } from "../../config/types.openclaw.js";
@@ -263,7 +264,11 @@ function groundedMarkdownToDiaryLines(markdown: string): string[] {
   return markdown
     .split("\n")
     .map((line) => line.replace(/^##\s+/, "").trimEnd())
-    .filter((line, index, lines) => line.length > 0 || (index > 0 && lines[index - 1]?.length > 0));
+    .filter(
+      (line, index, lines) =>
+        line.length > 0 ||
+        (index > 0 && expectDefined(lines[index - 1], "lines entry at index 1")?.length > 0),
+    );
 }
 
 async function listWorkspaceDailyFiles(memoryDir: string): Promise<string[]> {
@@ -435,7 +440,7 @@ function trimDreamingEntries(
     // Keep the public status payload bounded while preserving the comparator's best entries.
     let insertAt = selected.length;
     for (let index = 0; index < selected.length; index += 1) {
-      if (compare(entry, selected[index]) < 0) {
+      if (compare(entry, expectDefined(selected[index], "selected entry at index")) < 0) {
         insertAt = index;
         break;
       }
diff --git a/src/gateway/server-methods/models-auth-status.ts b/src/gateway/server-methods/models-auth-status.ts
index 41dfcde46876..14e2c47d5031 100644
--- a/src/gateway/server-methods/models-auth-status.ts
+++ b/src/gateway/server-methods/models-auth-status.ts
@@ -29,7 +29,7 @@ import { resolveProviderIdForAuth } from "../../agents/provider-auth-aliases.js"
 import type { OpenClawConfig } from "../../config/config.js";
 import { isSecretRef } from "../../config/types.secrets.js";
 import { loadProviderUsageSummary } from "../../infra/provider-usage.load.js";
-import { PROVIDER_LABELS, resolveUsageProviderId } from "../../infra/provider-usage.shared.js";
+import { providerUsageLabel, resolveUsageProviderId } from "../../infra/provider-usage.shared.js";
 import type {
   ProviderUsageBilling,
   ProviderUsageSnapshot,
@@ -204,8 +204,9 @@ function buildExpiry(
 
 function providerDisplayName(provider: string): string {
   const usageId = resolveUsageProviderId(provider);
-  if (usageId && PROVIDER_LABELS[usageId]) {
-    return PROVIDER_LABELS[usageId];
+  const usageLabel = usageId ? providerUsageLabel(usageId) : undefined;
+  if (usageLabel) {
+    return usageLabel;
   }
   return provider;
 }
diff --git a/src/gateway/server-methods/sessions-diff.ts b/src/gateway/server-methods/sessions-diff.ts
index 8baa956dd314..8a31efb3abb3 100644
--- a/src/gateway/server-methods/sessions-diff.ts
+++ b/src/gateway/server-methods/sessions-diff.ts
@@ -3,6 +3,7 @@
 // Control UI diff panel can render without shelling out client-side.
 import fs from "node:fs/promises";
 import nodePath from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import {
   validateSessionsDiffParams,
@@ -112,20 +113,20 @@ export function parseNumstatZ(text: string): Map<string, NumstatEntry> {
 function chunkPath(chunk: string): string | null {
   const newFile = /^\+\+\+ b\/(.+)$/m.exec(chunk);
   if (newFile) {
-    return newFile[1];
+    return expectDefined(newFile[1], "new file capture group 1");
   }
   // Deleted files have `+++ /dev/null`; key the chunk by the old path.
   const oldFile = /^--- a\/(.+)$/m.exec(chunk);
   if (oldFile) {
-    return oldFile[1];
+    return expectDefined(oldFile[1], "old file capture group 1");
   }
   // Pure renames and binary chunks have neither marker line.
   const renameTo = /^rename to (.+)$/m.exec(chunk);
   if (renameTo) {
-    return renameTo[1];
+    return expectDefined(renameTo[1], "rename to capture group 1");
   }
   const header = /^diff --git a\/.+ b\/(.+)$/m.exec(chunk);
-  return header ? header[1] : null;
+  return header ? expectDefined(header[1], "header capture group 1") : null;
 }
 
 /** Splits a multi-file `git diff --patch` into per-file chunks keyed by path. */
diff --git a/src/gateway/server-methods/sessions.ts b/src/gateway/server-methods/sessions.ts
index 40276f9baa7d..2a58986e1145 100644
--- a/src/gateway/server-methods/sessions.ts
+++ b/src/gateway/server-methods/sessions.ts
@@ -3,6 +3,7 @@
 import { randomUUID } from "node:crypto";
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeOptionalString,
   readStringValue,
@@ -412,7 +413,10 @@ async function createAgentMainSessionForSend(params: {
   let createResult:
     | { ok: boolean; payload?: { key?: string }; error?: ReturnType<typeof errorShape> }
     | undefined;
-  await sessionsHandlers["sessions.create"]({
+  await expectDefined(
+    sessionsHandlers["sessions.create"],
+    "sessions.create handler",
+  )({
     req: params.req,
     params: {
       key: params.canonicalKey,
@@ -592,7 +596,10 @@ async function interruptSessionRunIfActive(params: {
       canonicalKey: params.canonicalKey,
     });
 
-    await chatHandlers["chat.abort"]({
+    await expectDefined(
+      chatHandlers["chat.abort"],
+      "chat.abort handler",
+    )({
       req: params.req,
       params: {
         sessionKey: abortSessionKey,
@@ -695,7 +702,10 @@ async function handleSessionSend(params: {
       : undefined;
   const idempotencyKey = explicitIdempotencyKey ?? randomUUID();
   const dispatchChatSend = async (respond: RespondFn) => {
-    await chatHandlers["chat.send"]({
+    await expectDefined(
+      chatHandlers["chat.send"],
+      "chat.send handler",
+    )({
       req: params.req,
       params: {
         sessionKey: canonicalKey,
@@ -1466,7 +1476,10 @@ export const sessionsHandlers: GatewayRequestHandlers = {
                 sessionKey: key,
                 storePath,
               })) + 1;
-            await chatHandlers["chat.send"]({
+            await expectDefined(
+              chatHandlers["chat.send"],
+              "chat.send handler",
+            )({
               req,
               params: {
                 sessionKey: key,
@@ -2084,7 +2097,10 @@ export const sessionsHandlers: GatewayRequestHandlers = {
       }
     }
     let abortedRunId: string | null = null;
-    await chatHandlers["chat.abort"]({
+    await expectDefined(
+      chatHandlers["chat.abort"],
+      "chat.abort handler",
+    )({
       req,
       params: {
         sessionKey: abortSessionKey,
@@ -2590,7 +2606,11 @@ export const sessionsHandlers: GatewayRequestHandlers = {
         }
       | undefined;
     const abortSessionKey = target.canonicalKey ?? key;
-    await chatHandlers["chat.abort"]({
+    const chatAbort = chatHandlers["chat.abort"];
+    if (!chatAbort) {
+      throw new Error("chat.abort handler is not registered");
+    }
+    await chatAbort({
       req,
       params: {
         sessionKey: abortSessionKey,
diff --git a/src/gateway/server-methods/usage.ts b/src/gateway/server-methods/usage.ts
index 71d28644417f..6110824b310a 100644
--- a/src/gateway/server-methods/usage.ts
+++ b/src/gateway/server-methods/usage.ts
@@ -1,6 +1,7 @@
 // Usage gateway methods aggregate provider and session cost/token metrics from
 // caches, logs, session stores, and discovered transcript files.
 import fs from "node:fs";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import {
   ErrorCodes,
@@ -1424,8 +1425,11 @@ export const usageHandlers: GatewayRequestHandlers = {
         if (!summary) {
           continue;
         }
-        const session = agentSessions[index];
-        const merged = mergedEntries[session.entryIndex];
+        const session = expectDefined(agentSessions[index], "agent sessions entry at index");
+        const merged = expectDefined(
+          mergedEntries[session.entryIndex],
+          "merged entries entry at session.entry index",
+        );
         const usage = usageByEntryIndex[session.entryIndex] ?? createEmptySessionCostSummary();
         usage.sessionId = merged.sessionId;
         usage.sessionFile = merged.sessionFile;
@@ -1590,7 +1594,7 @@ export const usageHandlers: GatewayRequestHandlers = {
           providerOverride: merged.storeEntry?.providerOverride,
           modelProvider: merged.storeEntry?.modelProvider,
           model: merged.storeEntry?.model,
-          usage,
+          usage: expectDefined(usage, "session usage summary"),
           contextWeight: includeContextWeight
             ? (merged.storeEntry?.systemPromptReport ?? null)
             : undefined,
diff --git a/src/gateway/server-methods/web.ts b/src/gateway/server-methods/web.ts
index 2f4a618d4160..e14eace4a0ac 100644
--- a/src/gateway/server-methods/web.ts
+++ b/src/gateway/server-methods/web.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Web login methods delegate QR-login start/wait requests to the active channel
 // plugin that owns web login gateway methods.
 import {
@@ -52,11 +53,11 @@ function resolveMissingWebLoginPluginHint(context: GatewayRequestContext): strin
     return null;
   }
   if (hints.length === 1) {
-    return hints[0].repairHint;
+    return expectDefined(hints[0], "hints entry at 0").repairHint;
   }
   const labels = [...new Set(hints.map((hint) => hint.label))];
   const installCommands = [...new Set(hints.map((hint) => hint.installCommand))];
-  const doctorFixCommand = hints[0].doctorFixCommand;
+  const doctorFixCommand = expectDefined(hints[0], "hints entry at 0").doctorFixCommand;
   return `Configured official external channel plugins are missing for ${labels.join(", ")}. Install them with: ${installCommands.join("; ")}, or run: ${doctorFixCommand}.`;
 }
 
diff --git a/src/gateway/session-utils.fs.ts b/src/gateway/session-utils.fs.ts
index c10a780f1853..707bdd6e0210 100644
--- a/src/gateway/session-utils.fs.ts
+++ b/src/gateway/session-utils.fs.ts
@@ -2,6 +2,7 @@
 // Parses transcript JSONL files for messages, previews, counts, and usage metadata.
 import fs from "node:fs";
 import { StringDecoder } from "node:string_decoder";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   resolveIntegerOption,
   resolveNonNegativeIntegerOption,
@@ -329,7 +330,7 @@ function isOversizedTranscriptLine(line: string): boolean {
 
 function isJsonObjectFieldToken(source: string, tokenIndex: number): boolean {
   for (let index = tokenIndex - 1; index >= 0; index--) {
-    const char = source[index];
+    const char = source.charAt(index);
     if (/\s/.test(char)) {
       continue;
     }
@@ -972,7 +973,7 @@ export function capArrayByJsonBytes<T>(
   let bytes = 2 + parts.reduce((a, b) => a + b, 0) + (items.length - 1);
   let start = 0;
   while (bytes > maxBytes && start < items.length - 1) {
-    bytes -= parts[start] + 1;
+    bytes -= expectDefined(parts[start], "parts entry at start") + 1;
     start += 1;
   }
   const next = start > 0 ? items.slice(start) : items;
@@ -2076,7 +2077,7 @@ function readRecentMessagesFromTranscript(
 
     const collected: TranscriptPreviewMessage[] = [];
     for (let i = tailLines.length - 1; i >= 0; i--) {
-      const line = tailLines[i];
+      const line = expectDefined(tailLines[i], "tail lines entry at i");
       try {
         const parsed = JSON.parse(line);
         const msg = parsed?.message as TranscriptPreviewMessage | undefined;
diff --git a/src/gateway/session-utils.ts b/src/gateway/session-utils.ts
index cfd8e22041e7..364eb0f33bf4 100644
--- a/src/gateway/session-utils.ts
+++ b/src/gateway/session-utils.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Gateway session listing and projection helpers.
 // Normalizes persisted session stores into UI/RPC rows without mutating state.
 import {
@@ -2881,7 +2882,7 @@ export async function listSessionsFromStoreAsync(params: {
 
     const sessions: GatewaySessionRow[] = [];
     for (let i = 0; i < entries.length; i++) {
-      const [key, entry] = entries[i];
+      const [key, entry] = expectDefined(entries[i], "entries entry at i");
       const includeTranscriptFields = i < sessionListTranscriptFieldRows;
       const rowAgentId =
         key === "global" && typeof opts.agentId === "string"
diff --git a/src/gateway/sessions-resolve.ts b/src/gateway/sessions-resolve.ts
index 4c94034d912a..2f7f099e3654 100644
--- a/src/gateway/sessions-resolve.ts
+++ b/src/gateway/sessions-resolve.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Gateway sessions.resolve implementation helper.
 // Resolves key/sessionId/label selectors into one canonical session key.
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
@@ -261,10 +262,13 @@ export async function resolveSessionKeyFromResolveParams(params: {
     };
   }
 
-  const labelKey = list.sessions[0].key;
+  const labelKey = expectDefined(list.sessions[0], "sessions entry at 0").key;
   const agentCheckLabel = validateSessionAgentExists(cfg, labelKey, store[labelKey]);
   if (agentCheckLabel) {
     return agentCheckLabel;
   }
-  return { ok: true, key: list.sessions[0].key };
+  return {
+    ok: true,
+    key: expectDefined(list.sessions[0], "sessions entry at 0").key,
+  };
 }
diff --git a/src/gateway/talk-agent-consult.ts b/src/gateway/talk-agent-consult.ts
index 2dfe1da63e66..7f2a0bd8007c 100644
--- a/src/gateway/talk-agent-consult.ts
+++ b/src/gateway/talk-agent-consult.ts
@@ -1,6 +1,7 @@
 // Gateway Talk realtime agent-consult bridge.
 // Starts chat.send runs that answer realtime Talk tool calls.
 import { randomUUID } from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   ErrorCodes,
   errorShape,
@@ -80,7 +81,10 @@ export async function startTalkRealtimeAgentConsult(params: {
     { ok: true; result: unknown } | { ok: false; error: ErrorShape } | undefined
   >((resolve) => {
     let acknowledged = false;
-    const chatSendResult = chatHandlers["chat.send"]({
+    const chatSendResult = expectDefined(
+      chatHandlers["chat.send"],
+      "chat.send handler",
+    )({
       req: {
         type: "req",
         id: `${params.requestId}:talk-tool-call`,
@@ -159,9 +163,9 @@ export async function startTalkRealtimeAgentConsult(params: {
       relaySessionId: params.relaySessionId,
       connId: params.connId,
       sessionKey: params.sessionKey,
-      runId,
+      runId: expectDefined(runId, "talk agent run id"),
       callId: params.callId,
     });
   }
-  return { ok: true, runId, idempotencyKey };
+  return { ok: true, runId: expectDefined(runId, "talk agent run id"), idempotencyKey };
 }
diff --git a/src/gateway/talk.test-helpers.ts b/src/gateway/talk.test-helpers.ts
index 0b11d081f5b1..c1e2c6c77321 100644
--- a/src/gateway/talk.test-helpers.ts
+++ b/src/gateway/talk.test-helpers.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /**
  * Direct talk method invocation helpers for gateway speech tests.
  */
@@ -24,7 +25,10 @@ export async function invokeTalkSpeakDirect(params: Record<string, unknown>) {
         error?: { code?: string; message?: string; details?: unknown };
       }
     | undefined;
-  await talkHandlers["talk.speak"]({
+  await expectDefined(
+    talkHandlers["talk.speak"],
+    "talk.speak handler",
+  )({
     req: { type: "req", id: "test", method: "talk.speak", params },
     params,
     client: null,
diff --git a/src/gateway/test/server-sessions.test-helpers.ts b/src/gateway/test/server-sessions.test-helpers.ts
index 9af2a2c8089f..1e82e70e839b 100644
--- a/src/gateway/test/server-sessions.test-helpers.ts
+++ b/src/gateway/test/server-sessions.test-helpers.ts
@@ -5,6 +5,7 @@ import fsSync from "node:fs";
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import type { AssistantMessage, UserMessage } from "openclaw/plugin-sdk/llm";
 import { afterAll, beforeAll, beforeEach, expect, vi } from "vitest";
 import type { SessionEntry } from "../../config/sessions.js";
@@ -689,7 +690,10 @@ export async function directSessionReq<TPayload = unknown>(
   let result:
     | { ok: boolean; payload?: TPayload; error?: { code?: string; message?: string } }
     | undefined;
-  await sessionsHandlers[method]({
+  await expectDefined(
+    sessionsHandlers[method],
+    "sessions handlers entry at method",
+  )({
     req: {} as never,
     params,
     respond: (ok, payload, error) => {
diff --git a/src/gateway/worker-environments/service.ts b/src/gateway/worker-environments/service.ts
index 2944f8cc44ac..a342037c43da 100644
--- a/src/gateway/worker-environments/service.ts
+++ b/src/gateway/worker-environments/service.ts
@@ -1,4 +1,5 @@
 import { createHash } from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import {
   type WorkerAdmissionHandshake,
@@ -706,7 +707,10 @@ export function createWorkerEnvironmentService(options: WorkerEnvironmentService
       if (!profiles || !Object.hasOwn(profiles, normalizedProfileId)) {
         throw serviceError("profile_not_found", `Unknown worker profile: ${normalizedProfileId}`);
       }
-      const profile = profiles[normalizedProfileId];
+      const profile = expectDefined(
+        profiles[normalizedProfileId],
+        "profiles entry at normalized profile id",
+      );
       const provider = providerFor(profile.provider);
       const settings = requireWorkerProfile(profile.settings ?? {});
       const intent = store.createIntent({
diff --git a/src/hooks/bundled/session-memory/transcript.ts b/src/hooks/bundled/session-memory/transcript.ts
index f7f98621f88e..fe5850e52485 100644
--- a/src/hooks/bundled/session-memory/transcript.ts
+++ b/src/hooks/bundled/session-memory/transcript.ts
@@ -176,7 +176,11 @@ export async function getRecentSessionContentWithResetFallback(
       return primary;
     }
 
-    const latestResetPath = path.join(dir, resetCandidates[resetCandidates.length - 1]);
+    const latestReset = resetCandidates.at(-1);
+    if (latestReset === undefined) {
+      return primary;
+    }
+    const latestResetPath = path.join(dir, latestReset);
     return (await getRecentSessionContent(latestResetPath, messageCount)) || primary;
   } catch {
     return primary;
@@ -219,8 +223,9 @@ export async function findPreviousSessionFile(params: {
         .filter((name) => name.startsWith(`${canonicalFile}.reset.`))
         .toSorted()
         .toReversed();
-      if (canonicalResetVariants.length > 0) {
-        return path.join(params.sessionsDir, canonicalResetVariants[0]);
+      const [canonicalResetVariant] = canonicalResetVariants;
+      if (canonicalResetVariant !== undefined) {
+        return path.join(params.sessionsDir, canonicalResetVariant);
       }
 
       const topicVariants = files
@@ -232,8 +237,9 @@ export async function findPreviousSessionFile(params: {
         )
         .toSorted()
         .toReversed();
-      if (topicVariants.length > 0) {
-        return path.join(params.sessionsDir, topicVariants[0]);
+      const [topicVariant] = topicVariants;
+      if (topicVariant !== undefined) {
+        return path.join(params.sessionsDir, topicVariant);
       }
 
       const topicResetVariants = files
@@ -242,8 +248,9 @@ export async function findPreviousSessionFile(params: {
         )
         .toSorted()
         .toReversed();
-      if (topicResetVariants.length > 0) {
-        return path.join(params.sessionsDir, topicResetVariants[0]);
+      const [topicResetVariant] = topicResetVariants;
+      if (topicResetVariant !== undefined) {
+        return path.join(params.sessionsDir, topicResetVariant);
       }
     }
 
@@ -255,16 +262,18 @@ export async function findPreviousSessionFile(params: {
       .filter((name) => name.endsWith(".jsonl") && !name.includes(".reset."))
       .toSorted()
       .toReversed();
-    if (nonResetJsonl.length > 0) {
-      return path.join(params.sessionsDir, nonResetJsonl[0]);
+    const [nonResetFile] = nonResetJsonl;
+    if (nonResetFile !== undefined) {
+      return path.join(params.sessionsDir, nonResetFile);
     }
 
     const resetJsonl = files
       .filter((name) => name.includes(".jsonl.reset."))
       .toSorted()
       .toReversed();
-    if (resetJsonl.length > 0) {
-      return path.join(params.sessionsDir, resetJsonl[0]);
+    const [resetFile] = resetJsonl;
+    if (resetFile !== undefined) {
+      return path.join(params.sessionsDir, resetFile);
     }
   } catch {
     // Ignore directory read errors.
diff --git a/src/hooks/installs.ts b/src/hooks/installs.ts
index 9fbc926dadd4..a95dda3f9ba5 100644
--- a/src/hooks/installs.ts
+++ b/src/hooks/installs.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Hook install record helpers read and write installed hook metadata.
 import type { HookInstallRecord } from "../config/types.hooks.js";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
@@ -25,7 +26,7 @@ export function recordHookInstall(cfg: OpenClawConfig, update: HookInstallUpdate
         ...cfg.hooks?.internal,
         installs: {
           ...installs,
-          [hookId]: installs[hookId],
+          [hookId]: expectDefined(installs[hookId], "installs entry at hook id"),
         },
       },
     },
diff --git a/src/infra/approval-native-route-coordinator.ts b/src/infra/approval-native-route-coordinator.ts
index e2b6c58733f3..a6ba38c4fd5f 100644
--- a/src/infra/approval-native-route-coordinator.ts
+++ b/src/infra/approval-native-route-coordinator.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Coordinates native approval delivery routing and notices.
 import {
   normalizeLowercaseStringOrEmpty,
@@ -197,7 +198,7 @@ function resolveApprovalRouteNotice(params: {
     return {
       requestGateway:
         params.reports.find((report) => activeApprovalRouteRuntimes.has(report.runtimeId))
-          ?.requestGateway ?? params.reports[0].requestGateway,
+          ?.requestGateway ?? expectDefined(params.reports[0], "reports entry at 0").requestGateway,
       target,
       text: resolveApprovalDeliveryFailedNoticeText({
         approvalId: params.request.id,
diff --git a/src/infra/bonjour-discovery.ts b/src/infra/bonjour-discovery.ts
index b92abc92dbc3..4eec464d4fc4 100644
--- a/src/infra/bonjour-discovery.ts
+++ b/src/infra/bonjour-discovery.ts
@@ -1,4 +1,5 @@
 // Discovers gateways over Bonjour and normalizes service records.
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
 import {
   normalizeStringEntries,
@@ -526,7 +527,9 @@ function parseAvahiBrowse(stdout: string): GatewayBonjourBeacon[] {
     }
 
     if (trimmed.startsWith("txt =")) {
-      const tokens = Array.from(trimmed.matchAll(/"([^"]*)"/g), (m) => m[1]);
+      const tokens = Array.from(trimmed.matchAll(/"([^"]*)"/g), (match) =>
+        expectDefined(match.at(1), "Bonjour TXT token"),
+      );
       const txt = parseTxtTokens(tokens);
       current.txt = Object.keys(txt).length ? txt : undefined;
       if (txt.displayName) {
diff --git a/src/infra/command-explainer/extract.ts b/src/infra/command-explainer/extract.ts
index 5e9c8eb11876..8d03a7c27c16 100644
--- a/src/infra/command-explainer/extract.ts
+++ b/src/infra/command-explainer/extract.ts
@@ -421,7 +421,7 @@ function hasUnescapedDynamicPattern(text: string): boolean {
 function decodeUnquotedShellTextWithOffsets(text: string): DecodedShellText {
   const decoded: DecodedShellText = { value: "", sourceOffsets: [0] };
   for (let index = 0; index < text.length; index += 1) {
-    const ch = text[index];
+    const ch = text.charAt(index);
     const next = text[index + 1];
     if (ch === "\\" && next !== undefined) {
       if (next === "\r" && text[index + 2] === "\n") {
@@ -453,7 +453,7 @@ function decodeDoubleQuotedTextWithOffsets(text: string): DecodedShellText {
   const body = hasQuotes ? text.slice(1, -1) : text;
   const decoded: DecodedShellText = { value: "", sourceOffsets: [bodyStart] };
   for (let index = 0; index < body.length; index += 1) {
-    const ch = body[index];
+    const ch = body.charAt(index);
     const next = body[index + 1];
     const sourceOffset = bodyStart + index;
     if (ch === "\\" && next !== undefined) {
@@ -503,7 +503,7 @@ function decodeAnsiCStringWithOffsets(text: string): DecodedShellText {
   const body = hasQuotes ? text.slice(2, -1) : text;
   const decoded: DecodedShellText = { value: "", sourceOffsets: [bodyStart] };
   for (let index = 0; index < body.length; index += 1) {
-    const ch = body[index];
+    const ch = body.charAt(index);
     const sourceOffset = bodyStart + index;
     if (ch !== "\\") {
       appendDecodedText(decoded, ch, sourceOffset + 1);
diff --git a/src/infra/device-pairing.ts b/src/infra/device-pairing.ts
index 7af2a05ffde9..1f3b2488721f 100644
--- a/src/infra/device-pairing.ts
+++ b/src/infra/device-pairing.ts
@@ -1,5 +1,6 @@
 // Manages device pairing requests, approvals, and token issuance.
 import { randomUUID } from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeUniqueSingleOrTrimmedStringList } from "@openclaw/normalization-core/string-normalization";
 import { normalizeDeviceAuthScopes } from "../shared/device-auth.js";
 import {
@@ -677,9 +678,15 @@ function reconcilePendingPairingRequests<
 }): PendingPairingRequestResult<TPending> {
   if (
     params.existing.length === 1 &&
-    params.canRefreshSingle(params.existing[0], params.incoming)
+    params.canRefreshSingle(
+      expectDefined(params.existing[0], "existing entry at 0"),
+      params.incoming,
+    )
   ) {
-    const refreshed = params.refreshSingle(params.existing[0], params.incoming);
+    const refreshed = params.refreshSingle(
+      expectDefined(params.existing[0], "existing entry at 0"),
+      params.incoming,
+    );
     params.pendingById[refreshed.requestId] = refreshed;
     params.persist();
     return { status: "pending", request: refreshed, created: false };
diff --git a/src/infra/diagnostic-trace-context.ts b/src/infra/diagnostic-trace-context.ts
index c2a607689ed1..d725e6d6a4e6 100644
--- a/src/infra/diagnostic-trace-context.ts
+++ b/src/infra/diagnostic-trace-context.ts
@@ -1,6 +1,7 @@
 // Creates and propagates lightweight W3C diagnostic trace contexts.
 import { AsyncLocalStorage } from "node:async_hooks";
 import { randomBytes } from "node:crypto";
+import { expectDefined } from "@openclaw/normalization-core";
 
 const TRACEPARENT_VERSION = "00";
 const DEFAULT_TRACE_FLAGS = "01";
@@ -141,7 +142,7 @@ export function parseDiagnosticTraceparent(
   }
   const [version, traceId, spanId, traceFlags] = parts;
   if (
-    !TRACEPARENT_VERSION_RE.test(version) ||
+    !TRACEPARENT_VERSION_RE.test(expectDefined(version, "diagnostic trace context version")) ||
     version === "ff" ||
     (version === TRACEPARENT_VERSION && parts.length !== 4)
   ) {
diff --git a/src/infra/exec-allowlist-pattern.ts b/src/infra/exec-allowlist-pattern.ts
index 991ca9809482..43047734d774 100644
--- a/src/infra/exec-allowlist-pattern.ts
+++ b/src/infra/exec-allowlist-pattern.ts
@@ -59,7 +59,7 @@ function compileGlobRegex(pattern: string): RegExp {
   let regex = "^";
   let i = 0;
   while (i < pattern.length) {
-    const ch = pattern[i];
+    const ch = pattern.charAt(i);
     if (ch === "*") {
       const next = pattern[i + 1];
       if (next === "*") {
diff --git a/src/infra/exec-approval-command-display.ts b/src/infra/exec-approval-command-display.ts
index b38f3091235d..b10742578e49 100644
--- a/src/infra/exec-approval-command-display.ts
+++ b/src/infra/exec-approval-command-display.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 // Sanitizes command text before it is displayed in approval prompts.
 import {
@@ -119,7 +120,10 @@ function sanitizeExecApprovalDisplayTextInternal(
   const strippedMask = computeSensitiveRedactionBitmap(stripped, redaction);
   let bypassDetected = false;
   for (let i = 0; i < strippedMask.length; i++) {
-    if (strippedMask[i] && !rawMask[strippedToOrig[i]]) {
+    if (
+      strippedMask[i] &&
+      !rawMask[expectDefined(strippedToOrig[i], "stripped to orig entry at i")]
+    ) {
       bypassDetected = true;
       break;
     }
@@ -137,7 +141,7 @@ function sanitizeExecApprovalDisplayTextInternal(
   const unionMask = rawMask.slice();
   for (let i = 0; i < strippedMask.length; i++) {
     if (strippedMask[i]) {
-      unionMask[strippedToOrig[i]] = true;
+      unionMask[expectDefined(strippedToOrig[i], "stripped to orig entry at i")] = true;
     }
   }
   let out = "";
diff --git a/src/infra/exec-approval-reply.ts b/src/infra/exec-approval-reply.ts
index e836fc63d237..f9bfb3d9949f 100644
--- a/src/infra/exec-approval-reply.ts
+++ b/src/infra/exec-approval-reply.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeOptionalLowercaseString,
   normalizeOptionalString,
@@ -354,7 +355,7 @@ export function parseExecApprovalCommandText(
   }
   const rawDecision = normalizeOptionalLowercaseString(match[2]) ?? "";
   return {
-    approvalId: match[1],
+    approvalId: expectDefined(match[1], "exec approval reply regex capture 1"),
     decision:
       rawDecision === "always" ? "allow-always" : (rawDecision as ExecApprovalReplyDecision),
   };
diff --git a/src/infra/exec-control-command-guard.ts b/src/infra/exec-control-command-guard.ts
index b5c8471b52e0..2038de736e7f 100644
--- a/src/infra/exec-control-command-guard.ts
+++ b/src/infra/exec-control-command-guard.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { normalizeStringEntries } from "@openclaw/normalization-core/string-normalization";
 import { splitShellArgs } from "../utils/shell-argv.js";
@@ -20,7 +21,7 @@ function parseExecApprovalShellCommand(raw: string): ParsedExecApprovalCommand |
     return null;
   }
   return {
-    approvalId: match[1],
+    approvalId: expectDefined(match[1], "exec control command guard regex capture 1"),
     decision:
       normalizeLowercaseStringOrEmpty(match[2]) === "always"
         ? "allow-always"
@@ -57,7 +58,7 @@ function stripOpenClawPackageRunner(argv: string[]): string[] {
   if (commandName === "npx" || commandName === "bunx") {
     let idx = 1;
     while (idx < argv.length) {
-      const token = argv[idx];
+      const token = expectDefined(argv[idx], "argv entry at idx");
       if (token === "--") {
         idx += 1;
         break;
diff --git a/src/infra/exec-safe-bin-policy-profiles.ts b/src/infra/exec-safe-bin-policy-profiles.ts
index 6cfcd34d3a24..abf164f162bc 100644
--- a/src/infra/exec-safe-bin-policy-profiles.ts
+++ b/src/infra/exec-safe-bin-policy-profiles.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Defines safe-bin policy profile fixtures and metadata.
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { sortUniqueStrings } from "@openclaw/normalization-core/string-normalization";
@@ -392,7 +393,12 @@ export function renderSafeBinDeniedFlagsDocBullets(
   const deniedByBin = resolveSafeBinDeniedFlags(fixtures);
   const bins = Object.keys(deniedByBin).toSorted();
   return bins
-    .map((bin) => `- \`${bin}\`: ${deniedByBin[bin].map((flag) => `\`${flag}\``).join(", ")}`)
+    .map(
+      (bin) =>
+        `- \`${bin}\`: ${expectDefined(deniedByBin[bin], "denied by bin entry at bin")
+          .map((flag) => `\`${flag}\``)
+          .join(", ")}`,
+    )
     .join("\n");
 }
 
diff --git a/src/infra/exec-safe-bin-policy-validator.ts b/src/infra/exec-safe-bin-policy-validator.ts
index 51ca1bedaa14..2ad93302c34f 100644
--- a/src/infra/exec-safe-bin-policy-validator.ts
+++ b/src/infra/exec-safe-bin-policy-validator.ts
@@ -104,8 +104,7 @@ function consumeShortOptionClusterToken(params: {
   allowedBooleanFlags: ReadonlySet<string>;
   deniedFlags: ReadonlySet<string>;
 }): number {
-  for (let j = 0; j < params.flags.length; j += 1) {
-    const flag = params.flags[j];
+  for (const [j, flag] of params.flags.entries()) {
     if (params.deniedFlags.has(flag)) {
       return -1;
     }
diff --git a/src/infra/heartbeat-events-filter.ts b/src/infra/heartbeat-events-filter.ts
index 86b128822b09..75d17b27bdee 100644
--- a/src/infra/heartbeat-events-filter.ts
+++ b/src/infra/heartbeat-events-filter.ts
@@ -186,7 +186,7 @@ function isHeartbeatAckEvent(evt: string): boolean {
   if (suffix.length === 0) {
     return true;
   }
-  return !/[a-z0-9_]/.test(suffix[0]);
+  return !/[a-z0-9_]/.test(suffix.charAt(0));
 }
 
 function isHeartbeatNoiseEvent(evt: string): boolean {
diff --git a/src/infra/net/proxy-env.ts b/src/infra/net/proxy-env.ts
index 7dd14088f9f6..05ac01db13b4 100644
--- a/src/infra/net/proxy-env.ts
+++ b/src/infra/net/proxy-env.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Proxy environment helpers mirror undici EnvHttpProxyAgent selection while
 // adding OpenClaw NO_PROXY CIDR/wildcard bypass checks.
 import { readTrimmedStringAlias } from "../../utils/string-readers.js";
@@ -191,7 +192,7 @@ export function matchesNoProxy(targetUrl: string, env: NodeJS.ProcessEnv = proce
       if (!m) {
         continue;
       }
-      entryHost = m[1];
+      entryHost = expectDefined(m[1], "m capture group 1");
       entryPort = m[2];
     } else {
       const firstColonIdx = entry.indexOf(":");
@@ -261,7 +262,7 @@ function matchesIpv4NoProxyPattern(targetHost: string, entryHost: string): boole
 
   const cidrMatch = entryHost.match(/^(\d{1,3}(?:\.\d{1,3}){3})\/(\d{1,2})$/);
   if (cidrMatch) {
-    const network = parseIpv4Address(cidrMatch[1]);
+    const network = parseIpv4Address(expectDefined(cidrMatch[1], "cidr match capture group 1"));
     const prefixLength = Number(cidrMatch[2]);
     if (network === undefined || prefixLength < 0 || prefixLength > 32) {
       return false;
@@ -278,8 +279,7 @@ function matchesIpv4NoProxyPattern(targetHost: string, entryHost: string): boole
   if (patternParts.length > 4 || patternParts.length === 0) {
     return false;
   }
-  for (let index = 0; index < patternParts.length; index += 1) {
-    const part = patternParts[index];
+  for (const [index, part] of patternParts.entries()) {
     if (part === "*") {
       if (index === patternParts.length - 1) {
         return true;
diff --git a/src/infra/net/ssrf.ts b/src/infra/net/ssrf.ts
index 6a7ec6ec01f8..b1d8f6633d4b 100644
--- a/src/infra/net/ssrf.ts
+++ b/src/infra/net/ssrf.ts
@@ -17,6 +17,7 @@ import {
   parseCanonicalIpAddress,
   parseLooseIpAddress,
 } from "@openclaw/net-policy/ip";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeUniqueStringEntries } from "@openclaw/normalization-core/string-normalization";
 import type { Dispatcher } from "undici";
 import { normalizeHostname } from "./hostname.js";
@@ -532,7 +533,10 @@ export function createPinnedLookup(params: {
       cb(null, usable as LookupAddress[]);
       return;
     }
-    const chosen = usable[index % usable.length];
+    const chosen = expectDefined(
+      usable[index % usable.length],
+      "usable entry at index % usable.length",
+    );
     index += 1;
     cb(null, chosen.address, chosen.family);
   }) as typeof dnsLookupCb;
diff --git a/src/infra/outbound/channel-selection.ts b/src/infra/outbound/channel-selection.ts
index 77f61d8b4cac..1e0e75e68cd2 100644
--- a/src/infra/outbound/channel-selection.ts
+++ b/src/infra/outbound/channel-selection.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Channel selection chooses a deliverable message channel from explicit input,
 // tool context fallback, or configured plugin accounts.
 import { listChannelPlugins } from "../../channels/plugins/index.js";
@@ -279,7 +280,11 @@ export async function resolveMessageChannelSelection(params: {
 
   const configured = await listConfiguredMessageChannels(params.cfg);
   if (configured.length === 1) {
-    return { channel: configured[0], configured, source: "single-configured" };
+    return {
+      channel: expectDefined(configured[0], "configured entry at 0"),
+      configured,
+      source: "single-configured",
+    };
   }
   if (configured.length === 0) {
     const repairHints = listConfiguredOfficialExternalRepairHints(params.cfg);
diff --git a/src/infra/outbound/deliver.ts b/src/infra/outbound/deliver.ts
index c055295dea14..4e617ac3487b 100644
--- a/src/infra/outbound/deliver.ts
+++ b/src/infra/outbound/deliver.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Outbound delivery core runs plugin hooks, queue durability, channel adapter
 // sends, commit hooks, diagnostics, transcript mirroring, and payload outcomes.
 import { hasTrustedMessageAuditListeners } from "../../audit/message-audit-events.js";
@@ -1878,7 +1879,12 @@ async function deliverOutboundPayloadsCore(
                 availableReportedIndices.has(reported.resultIndex) &&
                 !coveredIndices.includes(reported.resultIndex) &&
                 results[reported.resultIndex]?.channel === delivery.channel &&
-                resultPlatformIds(results[reported.resultIndex]).has(receiptId),
+                resultPlatformIds(
+                  expectDefined(
+                    results[reported.resultIndex],
+                    "results entry at reported.result index",
+                  ),
+                ).has(receiptId),
             )
             .map((reported) => reported.resultIndex);
           // One receipt part covers one progress result. Repeated parts preserve
diff --git a/src/infra/outbound/envelope.ts b/src/infra/outbound/envelope.ts
index 08bc603c525c..457ae2a44536 100644
--- a/src/infra/outbound/envelope.ts
+++ b/src/infra/outbound/envelope.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Outbound envelopes wrap payload projections, metadata, and delivery JSON for
 // tool responses while flattening simple delivery-only results.
 import type { ReplyPayload } from "../../auto-reply/types.js";
@@ -32,7 +33,7 @@ export function buildOutboundResultEnvelope(
       ? undefined
       : params.payloads.length === 0
         ? []
-        : isOutboundPayloadJson(params.payloads[0])
+        : isOutboundPayloadJson(expectDefined(params.payloads[0], "payloads entry at 0"))
           ? [...(params.payloads as readonly OutboundPayloadJson[])]
           : normalizeOutboundPayloadsForJson(params.payloads as readonly ReplyPayload[]);
 
diff --git a/src/infra/outbound/format.ts b/src/infra/outbound/format.ts
index c97d04895b38..681f82a74236 100644
--- a/src/infra/outbound/format.ts
+++ b/src/infra/outbound/format.ts
@@ -1,6 +1,6 @@
 // Outbound delivery formatting produces human CLI summaries for direct and
 // gateway send results.
-import { getChatChannelMeta } from "../../channels/chat-meta.js";
+import { findChatChannelMeta } from "../../channels/chat-meta.js";
 import { getChannelPlugin } from "../../channels/plugins/index.js";
 import type { ChannelId } from "../../channels/plugins/types.public.js";
 import { normalizeChatChannelId } from "../../channels/registry.js";
@@ -32,7 +32,7 @@ const resolveChannelLabel = (channel: string) => {
   // Some legacy chat channels are not plugins; keep their human labels for CLI output.
   const normalized = normalizeChatChannelId(channel);
   if (normalized) {
-    return getChatChannelMeta(normalized).label;
+    return findChatChannelMeta(normalized)?.label ?? channel;
   }
   return channel;
 };
diff --git a/src/infra/outbound/outbound-session.test-helpers.ts b/src/infra/outbound/outbound-session.test-helpers.ts
index 3fcfa1e7a9dc..c382a7868195 100644
--- a/src/infra/outbound/outbound-session.test-helpers.ts
+++ b/src/infra/outbound/outbound-session.test-helpers.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Test helpers build minimal plugin registries for outbound session-route
 // scenarios without importing real channel implementations.
 import {
@@ -91,10 +92,13 @@ function parseForumTargetForTest(raw: string): {
     .replace(/^group:/i, "");
   const prefixedTopic = /^([^:]+):topic:(\d+)$/i.exec(trimmed);
   if (prefixedTopic) {
-    const chatId = prefixedTopic[1];
+    const chatId = expectDefined(prefixedTopic[1], "prefixed topic capture group 1");
     return {
       chatId,
-      messageThreadId: Number.parseInt(prefixedTopic[2], 10),
+      messageThreadId: Number.parseInt(
+        expectDefined(prefixedTopic[2], "prefixed topic capture group 2"),
+        10,
+      ),
       chatType: chatId.startsWith("-") ? "group" : "direct",
     };
   }
@@ -113,7 +117,7 @@ function parseForumThreadIdForTest(threadId?: string | number | null): number |
   if (!topicMatch) {
     return undefined;
   }
-  return Number.parseInt(topicMatch[1], 10);
+  return Number.parseInt(expectDefined(topicMatch[1], "topic match capture group 1"), 10);
 }
 
 function buildForumGroupPeerIdForTest(chatId: string, messageThreadId?: number): string {
@@ -398,7 +402,9 @@ function resolveLocalChatOutboundSessionRouteForTest(params: ChannelOutboundSess
     return null;
   }
   const match = /^(chat_guid|chat_identifier|chat_id):(.+)$/i.exec(stripped);
-  const rawId = match ? match[2].trim() : stripped.trim();
+  const rawId = match
+    ? expectDefined(match[2], "outbound session.test helpers regex capture 2").trim()
+    : stripped.trim();
   if (!rawId) {
     return null;
   }
diff --git a/src/infra/outbound/target-resolver.ts b/src/infra/outbound/target-resolver.ts
index 29b86eb0088c..b6ecf586bef6 100644
--- a/src/infra/outbound/target-resolver.ts
+++ b/src/infra/outbound/target-resolver.ts
@@ -479,6 +479,9 @@ export async function resolveMessagingTarget(params: {
   });
   if (match.kind === "single") {
     const entry = match.entry;
+    if (!entry) {
+      throw new Error("Single directory match is missing its entry");
+    }
     return {
       ok: true,
       target: {
diff --git a/src/infra/outbound/targets.ts b/src/infra/outbound/targets.ts
index 80bd13d31279..e9a67444f7a9 100644
--- a/src/infra/outbound/targets.ts
+++ b/src/infra/outbound/targets.ts
@@ -61,6 +61,7 @@ export type HeartbeatSenderContext = {
 
 export type { OutboundTargetResolution } from "./targets-resolve-shared.js";
 export { resolveSessionDeliveryTarget, type SessionDeliveryTarget } from "./targets-session.js";
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveSessionDeliveryTarget, type SessionDeliveryTarget } from "./targets-session.js";
 
 /** Resolves a user-supplied outbound destination through the channel plugin. */
@@ -549,5 +550,5 @@ export function resolveHeartbeatSenderContext(params: {
     provider,
   });
 
-  return { sender, provider, allowFrom };
+  return { sender: expectDefined(sender, "resolved sender"), provider, allowFrom };
 }
diff --git a/src/infra/ports-format.ts b/src/infra/ports-format.ts
index c27d545db1cd..002db61d0bba 100644
--- a/src/infra/ports-format.ts
+++ b/src/infra/ports-format.ts
@@ -1,5 +1,6 @@
 // Formats port probe results for diagnostics and CLI output.
 import net from "node:net";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { formatCliCommand } from "../cli/command-format.js";
 import type { PortListener, PortListenerKind, PortUsage } from "./ports-types.js";
@@ -49,7 +50,10 @@ function parseListenerAddress(address: string): { host: string; port: number } |
   const normalized = trimmed.replace(/^tcp6?\s+/i, "").replace(/\s*\(listen\)\s*$/i, "");
   const bracketMatch = normalized.match(/^\[([^\]]+)\]:(\d+)$/);
   if (bracketMatch) {
-    const port = Number.parseInt(bracketMatch[2], 10);
+    const port = Number.parseInt(
+      expectDefined(bracketMatch[2], "bracket match capture group 2"),
+      10,
+    );
     return Number.isFinite(port)
       ? { host: normalizeLowercaseStringOrEmpty(bracketMatch[1]), port }
       : null;
diff --git a/src/infra/ports-inspect.ts b/src/infra/ports-inspect.ts
index 1ca588e3d2a7..f4dbc4a1f6e1 100644
--- a/src/infra/ports-inspect.ts
+++ b/src/infra/ports-inspect.ts
@@ -1,5 +1,6 @@
 // Inspects gateway port listeners and connection state.
 import os from "node:os";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { runCommandWithTimeout } from "../process/exec.js";
 import { parseStrictPositiveInteger } from "./parse-finite-number.js";
@@ -182,7 +183,7 @@ function parseSsConnections(output: string, port: number): PortConnection[] {
     };
     const pidMatch = line.match(/pid=(\d+)/);
     if (pidMatch) {
-      const pid = Number.parseInt(pidMatch[1], 10);
+      const pid = Number.parseInt(expectDefined(pidMatch[1], "pid match capture group 1"), 10);
       if (Number.isFinite(pid)) {
         connection.pid = pid;
       }
@@ -330,7 +331,7 @@ function parseSsListeners(output: string, port: number): PortListener[] {
     };
     const pidMatch = line.match(/pid=(\d+)/);
     if (pidMatch) {
-      const pid = Number.parseInt(pidMatch[1], 10);
+      const pid = Number.parseInt(expectDefined(pidMatch[1], "pid match capture group 1"), 10);
       if (Number.isFinite(pid)) {
         listener.pid = pid;
       }
diff --git a/src/infra/ports-netstat.ts b/src/infra/ports-netstat.ts
index 304765a61b91..44a81f9133b5 100644
--- a/src/infra/ports-netstat.ts
+++ b/src/infra/ports-netstat.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 import { parseStrictPositiveInteger } from "./parse-finite-number.js";
 import type { PortListener } from "./ports-types.js";
 
@@ -21,7 +22,12 @@ export function parseTcpEndpoint(raw: string): { host: string; port: number } |
   const bracketMatch = endpoint.match(/^\[([^\]]+)\]:(\d+)$/);
   if (bracketMatch) {
     const port = parseTcpPort(bracketMatch[2]);
-    return port === null ? null : { host: normalizeTcpHost(bracketMatch[1]), port };
+    return port === null
+      ? null
+      : {
+          host: normalizeTcpHost(expectDefined(bracketMatch[1], "bracket match capture group 1")),
+          port,
+        };
   }
   const lastColon = endpoint.lastIndexOf(":");
   if (lastColon <= 0 || lastColon >= endpoint.length - 1) {
diff --git a/src/infra/provider-usage.fetch.gemini.ts b/src/infra/provider-usage.fetch.gemini.ts
index 30e308e7c02a..152046f1aac4 100644
--- a/src/infra/provider-usage.fetch.gemini.ts
+++ b/src/infra/provider-usage.fetch.gemini.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Fetches Gemini provider usage windows.
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import {
@@ -6,7 +7,7 @@ import {
   fetchJson,
   readUsageJson,
 } from "./provider-usage.fetch.shared.js";
-import { clampPercent, PROVIDER_LABELS } from "./provider-usage.shared.js";
+import { clampPercent, providerUsageLabel } from "./provider-usage.shared.js";
 import type {
   ProviderUsageSnapshot,
   UsageProviderId,
@@ -95,5 +96,9 @@ export async function fetchGeminiUsage(
     });
   }
 
-  return { provider, displayName: PROVIDER_LABELS[provider], windows };
+  return {
+    provider,
+    displayName: expectDefined(providerUsageLabel(provider), "gemini provider usage label"),
+    windows,
+  };
 }
diff --git a/src/infra/provider-usage.shared.ts b/src/infra/provider-usage.shared.ts
index 26556ee33ddc..99a07b9f419f 100644
--- a/src/infra/provider-usage.shared.ts
+++ b/src/infra/provider-usage.shared.ts
@@ -6,7 +6,7 @@ import type { UsageProviderId } from "./provider-usage.types.js";
 /** Default timeout for provider usage collection. */
 export const DEFAULT_TIMEOUT_MS = 5000;
 
-export const PROVIDER_LABELS: Readonly<Record<string, string>> = {
+export const PROVIDER_LABELS = {
   anthropic: "Claude",
   clawrouter: "ClawRouter",
   deepseek: "DeepSeek",
@@ -19,10 +19,16 @@ export const PROVIDER_LABELS: Readonly<Record<string, string>> = {
   xiaomi: "Xiaomi",
   "xiaomi-token-plan": "Xiaomi Token Plan",
   zai: "z.ai",
-};
+} as const satisfies Readonly<Record<string, string>>;
+
+/** Dynamic-key lookup view; closed-key reads should use PROVIDER_LABELS directly. */
+export function providerUsageLabel(provider: string): string | undefined {
+  const labels: Readonly<Record<string, string | undefined>> = PROVIDER_LABELS;
+  return labels[provider];
+}
 
 export function resolveProviderUsageDisplayName(provider: string): string {
-  return PROVIDER_LABELS[provider] ?? provider;
+  return providerUsageLabel(provider) ?? provider;
 }
 
 /** Returns true for providers whose usage endpoint is only meaningful with OAuth/token auth. */
diff --git a/src/infra/push-web.ts b/src/infra/push-web.ts
index 255536d99796..087c13f1efe4 100644
--- a/src/infra/push-web.ts
+++ b/src/infra/push-web.ts
@@ -1,6 +1,7 @@
 // Stores and verifies web push subscriptions and delivery payloads.
 import { randomUUID } from "node:crypto";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveStateDir } from "../config/paths.js";
 import { createLazyRuntimeModule } from "../shared/lazy-runtime.js";
 import { sha256HexPrefix } from "./crypto-digest.js";
@@ -284,7 +285,8 @@ export async function broadcastWebPush(
       ? r.value
       : {
           ok: false,
-          subscriptionId: subscriptions[i].subscriptionId,
+          subscriptionId: expectDefined(subscriptions[i], "subscriptions entry at i")
+            .subscriptionId,
           error: r.reason instanceof Error ? r.reason.message : "unknown error",
         },
   );
@@ -293,7 +295,7 @@ export async function broadcastWebPush(
   const expiredEndpoints = mapped
     .map((result, i) => ({ result, sub: subscriptions[i] }))
     .filter(({ result }) => !result.ok && (result.statusCode === 410 || result.statusCode === 404))
-    .map(({ sub }) => sub.endpoint);
+    .map(({ sub }) => expectDefined(sub, "push web sub").endpoint);
 
   if (expiredEndpoints.length > 0) {
     await Promise.allSettled(
diff --git a/src/infra/runtime-guard.ts b/src/infra/runtime-guard.ts
index 6e6f957d4e5f..1d191f6d2c1b 100644
--- a/src/infra/runtime-guard.ts
+++ b/src/infra/runtime-guard.ts
@@ -1,5 +1,6 @@
 // Validates the current runtime against OpenClaw's Node engine floor.
 import process from "node:process";
+import { expectDefined } from "@openclaw/normalization-core";
 import { defaultRuntime, type RuntimeEnv } from "../runtime.js";
 
 type RuntimeKind = "node" | "unknown";
@@ -37,9 +38,9 @@ export function parseSemver(version: string | null): Semver | null {
   }
   const [, major, minor, patch] = match;
   return {
-    major: Number.parseInt(major, 10),
-    minor: Number.parseInt(minor, 10),
-    patch: Number.parseInt(patch, 10),
+    major: Number.parseInt(expectDefined(major, "runtime guard major"), 10),
+    minor: Number.parseInt(expectDefined(minor, "runtime guard minor"), 10),
+    patch: Number.parseInt(expectDefined(patch, "runtime guard patch"), 10),
   };
 }
 
diff --git a/src/infra/session-cost-usage.ts b/src/infra/session-cost-usage.ts
index 2c5092ca1513..50810490d975 100644
--- a/src/infra/session-cost-usage.ts
+++ b/src/infra/session-cost-usage.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs";
 import path from "node:path";
 import readline from "node:readline";
+import { expectDefined } from "@openclaw/normalization-core";
 import { asFiniteNumber } from "@openclaw/normalization-core/number-coercion";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
@@ -1229,9 +1230,9 @@ const computeLatencyStats = (values: number[]): SessionLatencyStats | undefined
   return {
     count,
     avgMs: total / count,
-    p95Ms: sorted[p95Index] ?? sorted[count - 1],
-    minMs: sorted[0],
-    maxMs: sorted[count - 1],
+    p95Ms: sorted[p95Index] ?? expectDefined(sorted[count - 1], "last latency sample"),
+    minMs: expectDefined(sorted[0], "sorted entry at 0"),
+    maxMs: expectDefined(sorted[count - 1], "sorted entry at count 1"),
   };
 };
 
diff --git a/src/infra/sqlite-wal.ts b/src/infra/sqlite-wal.ts
index a1463bdd31f7..ce6a7ed22151 100644
--- a/src/infra/sqlite-wal.ts
+++ b/src/infra/sqlite-wal.ts
@@ -3,6 +3,7 @@ import childProcess from "node:child_process";
 import fs from "node:fs";
 import path from "node:path";
 import type { DatabaseSync } from "node:sqlite";
+import { expectDefined } from "@openclaw/normalization-core";
 import { MAX_TIMER_TIMEOUT_MS } from "../shared/number-coercion.js";
 import { isSqliteLockError } from "./sqlite-transaction.js";
 
@@ -149,12 +150,20 @@ function parseMountCommandEntries(contents: string): MountEntry[] {
   for (const line of contents.split("\n")) {
     const linuxMatch = /^(.+) on (.+) type ([^,\s)]+) \(/.exec(line);
     if (linuxMatch) {
-      entries.push({ source: linuxMatch[1], mountPoint: linuxMatch[2], fsType: linuxMatch[3] });
+      entries.push({
+        source: linuxMatch[1],
+        mountPoint: expectDefined(linuxMatch[2], "linux match capture group 2"),
+        fsType: expectDefined(linuxMatch[3], "linux match capture group 3"),
+      });
       continue;
     }
     const bsdMatch = /^(.+) on (.+) \(([^,\s)]+)/.exec(line);
     if (bsdMatch) {
-      entries.push({ source: bsdMatch[1], mountPoint: bsdMatch[2], fsType: bsdMatch[3] });
+      entries.push({
+        source: bsdMatch[1],
+        mountPoint: expectDefined(bsdMatch[2], "bsd match capture group 2"),
+        fsType: expectDefined(bsdMatch[3], "bsd match capture group 3"),
+      });
     }
   }
   return entries;
diff --git a/src/infra/stable-node-path.ts b/src/infra/stable-node-path.ts
index a3a73fa594ca..1cbba25df8c8 100644
--- a/src/infra/stable-node-path.ts
+++ b/src/infra/stable-node-path.ts
@@ -1,6 +1,7 @@
 // Resolves Homebrew Node binary paths to stable symlink targets.
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 
 /**
  * Homebrew Cellar paths (e.g. /opt/homebrew/Cellar/node/25.7.0/bin/node)
@@ -16,8 +17,8 @@ export async function resolveStableNodePath(nodePath: string): Promise<string> {
   if (!cellarMatch) {
     return nodePath;
   }
-  const prefix = cellarMatch[1]; // e.g. /opt/homebrew
-  const formula = cellarMatch[2]; // e.g. "node" or "node@22"
+  const prefix = expectDefined(cellarMatch[1], "cellar match capture group 1"); // e.g. /opt/homebrew
+  const formula = expectDefined(cellarMatch[2], "cellar match capture group 2"); // e.g. "node" or "node@22"
   const pathModule = nodePath.includes("\\") ? path.win32 : path.posix;
 
   // Try the Homebrew opt symlink first — works for both default and versioned formulas.
diff --git a/src/infra/state-migrations.ts b/src/infra/state-migrations.ts
index 576bf13de18a..8c6b6868aa3d 100644
--- a/src/infra/state-migrations.ts
+++ b/src/infra/state-migrations.ts
@@ -3,6 +3,7 @@ import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
 import type { DatabaseSync, SQLInputValue } from "node:sqlite";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { writeAcpSessionMetaForMigration } from "../acp/runtime/session-meta.js";
 import { resolveDefaultAgentId } from "../agents/agent-scope.js";
@@ -1171,12 +1172,13 @@ async function migrateLegacyTaskRunsSidecar(params: {
           "terminal_outcome",
         ];
         for (const row of taskRows) {
+          const taskId = legacyKeyValue(expectDefined(row.task_id, "task migration row key"));
           const existing = db
             .prepare(`SELECT ${taskColumns.join(", ")} FROM task_runs WHERE task_id = ?`)
-            .get(legacyKeyValue(row.task_id));
+            .get(taskId);
           if (existing) {
             if (!legacyRowsMatch(existing as Record<string, unknown>, row, taskColumns)) {
-              conflicts.push(legacyKeyValue(row.task_id));
+              conflicts.push(taskId);
             }
             continue;
           }
@@ -1185,20 +1187,19 @@ async function migrateLegacyTaskRunsSidecar(params: {
         }
         const deliveryColumns = ["requester_origin_json", "last_notified_event_at"];
         for (const row of deliveryRows) {
+          const taskId = legacyKeyValue(expectDefined(row.task_id, "delivery migration row key"));
           const existing = db
             .prepare(
               `SELECT requester_origin_json, last_notified_event_at FROM task_delivery_state WHERE task_id = ?`,
             )
-            .get(legacyKeyValue(row.task_id));
+            .get(taskId);
           if (existing) {
             if (!legacyRowsMatch(existing as Record<string, unknown>, row, deliveryColumns)) {
-              conflicts.push(`${legacyKeyValue(row.task_id)}/delivery`);
+              conflicts.push(`${taskId}/delivery`);
             }
             continue;
           }
-          const taskExists = db
-            .prepare("SELECT 1 FROM task_runs WHERE task_id = ?")
-            .get(legacyKeyValue(row.task_id));
+          const taskExists = db.prepare("SELECT 1 FROM task_runs WHERE task_id = ?").get(taskId);
           if (!taskExists) {
             skippedOrphanDeliveryStates++;
             continue;
@@ -1296,12 +1297,13 @@ async function migrateLegacyFlowRunsSidecar(params: {
           "ended_at",
         ];
         for (const row of rows) {
+          const flowId = legacyKeyValue(expectDefined(row.flow_id, "flow migration row key"));
           const existing = db
             .prepare(`SELECT ${columns.join(", ")} FROM flow_runs WHERE flow_id = ?`)
-            .get(legacyKeyValue(row.flow_id));
+            .get(flowId);
           if (existing) {
             if (!legacyRowsMatch(existing as Record<string, unknown>, row, columns)) {
-              conflicts.push(legacyKeyValue(row.flow_id));
+              conflicts.push(flowId);
             }
             continue;
           }
diff --git a/src/infra/system-events.ts b/src/infra/system-events.ts
index 1103c961bca0..f3580d6f415f 100644
--- a/src/infra/system-events.ts
+++ b/src/infra/system-events.ts
@@ -2,6 +2,7 @@
 // prefixed to the next prompt. We intentionally avoid persistence to keep
 // events ephemeral. Events are session-scoped and require an explicit key.
 
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeOptionalLowercaseString,
   normalizeOptionalString,
@@ -186,7 +187,7 @@ function resetQueueState(key: string, entry: SessionQueue) {
     return;
   }
   for (let index = entry.queue.length - 1; index >= 0; index -= 1) {
-    const contextKey = entry.queue[index].contextKey ?? null;
+    const contextKey = expectDefined(entry.queue[index], "queue entry at index").contextKey ?? null;
     if (contextKey !== null) {
       entry.lastContextKey = contextKey;
       return;
@@ -206,7 +207,9 @@ export function consumeSystemEventEntries(
   }
   if (
     consumedEntries.length > entry.queue.length ||
-    !consumedEntries.every((event, index) => areSystemEventsEqual(entry.queue[index], event))
+    !consumedEntries.every((event, index) =>
+      areSystemEventsEqual(expectDefined(entry.queue[index], "queue entry at index"), event),
+    )
   ) {
     return [];
   }
diff --git a/src/infra/system-presence.ts b/src/infra/system-presence.ts
index 25c904134e6b..cebab6406469 100644
--- a/src/infra/system-presence.ts
+++ b/src/infra/system-presence.ts
@@ -145,6 +145,16 @@ function parsePresence(text: string): SystemPresence {
     return { text: trimmed, ts: Date.now() };
   }
   const [, host, ip, version, lastInputStr, mode, reasonRaw] = match;
+  if (
+    host === undefined ||
+    ip === undefined ||
+    version === undefined ||
+    lastInputStr === undefined ||
+    mode === undefined ||
+    reasonRaw === undefined
+  ) {
+    return { text: trimmed, ts: Date.now() };
+  }
   const lastInputSeconds = Number.parseInt(lastInputStr, 10);
   const reason = reasonRaw.trim();
   return {
@@ -283,8 +293,8 @@ export function listSystemPresence(): SystemPresence[] {
   if (entries.size > MAX_ENTRIES) {
     const sorted = [...entries.entries()].toSorted((a, b) => a[1].ts - b[1].ts);
     const toDrop = entries.size - MAX_ENTRIES;
-    for (let i = 0; i < toDrop; i++) {
-      entries.delete(sorted[i][0]);
+    for (const [key] of sorted.slice(0, toDrop)) {
+      entries.delete(key);
     }
   }
   touchSelfPresence();
diff --git a/src/infra/tailscale.ts b/src/infra/tailscale.ts
index fd0f6cc8b05d..aaf764048ae4 100644
--- a/src/infra/tailscale.ts
+++ b/src/infra/tailscale.ts
@@ -146,8 +146,9 @@ export async function getTailnetHostname(exec: typeof runExec = runExec, detecte
       if (dns && dns.length > 0) {
         return dns.replace(/\.$/, "");
       }
-      if (ips.length > 0) {
-        return ips[0];
+      const [firstIp] = ips;
+      if (firstIp !== undefined) {
+        return firstIp;
       }
       throw new Error("Could not determine Tailscale DNS or IP");
     } catch (err) {
diff --git a/src/infra/widearea-dns.ts b/src/infra/widearea-dns.ts
index 07a958902459..3ce52b70c4a2 100644
--- a/src/infra/widearea-dns.ts
+++ b/src/infra/widearea-dns.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { CONFIG_DIR, ensureDir } from "../utils.js";
 
@@ -102,7 +103,7 @@ function extractSerial(zoneText: string): number | null {
   if (!match) {
     return null;
   }
-  const parsed = Number.parseInt(match[1], 10);
+  const parsed = Number.parseInt(expectDefined(match[1], "widearea dns regex capture 1"), 10);
   return Number.isFinite(parsed) ? parsed : null;
 }
 
diff --git a/src/infra/windows-encoding.ts b/src/infra/windows-encoding.ts
index ed474d7f03b1..cc7d8a85b599 100644
--- a/src/infra/windows-encoding.ts
+++ b/src/infra/windows-encoding.ts
@@ -212,13 +212,11 @@ export function createWindowsOutputDecoder(params?: {
 function getTrailingIncompleteUtf8Bytes(buffer: Buffer): Buffer {
   let index = buffer.length - 1;
   let continuationBytes = 0;
-  while (
-    index >= 0 &&
-    buffer[index] !== undefined &&
-    buffer[index] >= 0x80 &&
-    buffer[index] <= 0xbf &&
-    continuationBytes < 3
-  ) {
+  while (index >= 0 && continuationBytes < 3) {
+    const byte = buffer.at(index);
+    if (byte === undefined || byte < 0x80 || byte > 0xbf) {
+      break;
+    }
     continuationBytes += 1;
     index -= 1;
   }
@@ -226,7 +224,10 @@ function getTrailingIncompleteUtf8Bytes(buffer: Buffer): Buffer {
     return buffer;
   }
 
-  const leadByte = buffer[index];
+  const leadByte = buffer.at(index);
+  if (leadByte === undefined) {
+    return Buffer.alloc(0);
+  }
   const sequenceLength = getUtf8SequenceLength(leadByte);
   if (sequenceLength <= 1) {
     return Buffer.alloc(0);
diff --git a/src/infra/windows-shell-command.ts b/src/infra/windows-shell-command.ts
index ff499cc7d7f9..7641c9b6ad74 100644
--- a/src/infra/windows-shell-command.ts
+++ b/src/infra/windows-shell-command.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import type { ExecCommandAnalysis } from "./exec-command-analysis-types.js";
 import { resolveCommandResolutionFromArgv } from "./exec-command-resolution.js";
@@ -27,7 +28,7 @@ function findWindowsUnsupportedToken(command: string): string | null {
   // cmd.exe does not recognise single quotes, so they are not treated as safe
   // quoting for this cross-host safety check.
   for (let i = 0; i < command.length; i++) {
-    const ch = command[i];
+    const ch = command.charAt(i);
     if (ch === '"') {
       inDouble = !inDouble;
       continue;
@@ -68,7 +69,7 @@ export function tokenizeWindowsSegment(segment: string): string[] | null {
   };
 
   for (let i = 0; i < segment.length; i += 1) {
-    const ch = segment[i];
+    const ch = segment.charAt(i);
     if (ch === '"' && !inSingle) {
       if (!inDouble) {
         wasQuoted = true;
@@ -118,7 +119,7 @@ function stripWindowsShellWrapper(command: string): string {
 function stripWindowsShellWrapperOnce(command: string): string {
   const psCallMatch = command.match(/^&\s+(.+)$/s);
   if (psCallMatch) {
-    return psCallMatch[1];
+    return expectDefined(psCallMatch[1], "ps call match capture group 1");
   }
 
   const psFlags =
@@ -129,19 +130,22 @@ function stripWindowsShellWrapperOnce(command: string): string {
     new RegExp(`^(?:powershell|pwsh)(?:\\.exe)?\\s+${psFlags}${psCommandFlag}\\s+"(.+)"$`, "is"),
   );
   if (psInvokeMatch) {
-    return psInvokeMatch[1].replace(/""/g, '"');
+    return expectDefined(psInvokeMatch[1], "ps invoke match capture group 1").replace(/""/g, '"');
   }
   const psInvokeSingleQuote = command.match(
     new RegExp(`^(?:powershell|pwsh)(?:\\.exe)?\\s+${psFlags}${psCommandFlag}\\s+'(.+)'$`, "is"),
   );
   if (psInvokeSingleQuote) {
-    return psInvokeSingleQuote[1].replace(/''/g, "'");
+    return expectDefined(psInvokeSingleQuote[1], "ps invoke single quote capture group 1").replace(
+      /''/g,
+      "'",
+    );
   }
   const psInvokeNoQuote = command.match(
     new RegExp(`^(?:powershell|pwsh)(?:\\.exe)?\\s+${psFlags}${psCommandFlag}\\s+(.+)$`, "is"),
   );
   if (psInvokeNoQuote) {
-    return psInvokeNoQuote[1];
+    return expectDefined(psInvokeNoQuote[1], "ps invoke no quote capture group 1");
   }
 
   // `cmd /c` stays intact because PowerShell execution would change cmd.exe
diff --git a/src/llm/utils/oauth/github-copilot.ts b/src/llm/utils/oauth/github-copilot.ts
index 9568f3be2533..870d30de9c8f 100644
--- a/src/llm/utils/oauth/github-copilot.ts
+++ b/src/llm/utils/oauth/github-copilot.ts
@@ -2,6 +2,7 @@
  * GitHub Copilot OAuth flow
  */
 
+import { expectDefined } from "@openclaw/normalization-core";
 import { resolveTimerTimeoutMs } from "@openclaw/normalization-core/number-coercion";
 import {
   assertOkOrThrowProviderError,
@@ -109,7 +110,7 @@ function getBaseUrlFromToken(token: string): string | null {
   if (!match) {
     return null;
   }
-  const proxyHost = match[1];
+  const proxyHost = expectDefined(match[1], "github copilot regex capture 1");
   // Convert proxy.xxx to api.xxx
   const apiHost = proxyHost.replace(/^proxy\./, "api.");
   return `https://${apiHost}`;
diff --git a/src/logger.ts b/src/logger.ts
index 20cd30f32001..fa2f5808a72d 100644
--- a/src/logger.ts
+++ b/src/logger.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Provides root logger helpers and themed terminal output.
 import { theme } from "../packages/terminal-core/src/theme.js";
 import { isVerbose } from "./global-state.js";
@@ -12,7 +13,11 @@ function splitSubsystem(message: string) {
   if (!match) {
     return null;
   }
-  const [, subsystem, rest] = match;
+  const subsystem = match.at(1);
+  const rest = match.at(2);
+  if (subsystem === undefined || rest === undefined) {
+    return null;
+  }
   return { subsystem, rest };
 }
 
@@ -29,7 +34,11 @@ function logWithSubsystem(params: {
 }) {
   const parsed = params.runtime === defaultRuntime ? splitSubsystem(params.message) : null;
   if (parsed) {
-    createSubsystemLogger(parsed.subsystem)[params.subsystemMethod](parsed.rest);
+    const method = expectDefined(
+      createSubsystemLogger(parsed.subsystem)[params.subsystemMethod],
+      "subsystem logger method",
+    );
+    method(parsed.rest);
     return;
   }
   params.runtime[params.runtimeMethod](params.runtimeFormatter(params.message));
diff --git a/src/logging/diagnostic-session-context.ts b/src/logging/diagnostic-session-context.ts
index d87158e7a24f..0b34a200fbdb 100644
--- a/src/logging/diagnostic-session-context.ts
+++ b/src/logging/diagnostic-session-context.ts
@@ -1,6 +1,7 @@
 // Diagnostic session context helpers capture session metadata for support bundles.
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { resolveStateDir } from "../config/paths.js";
 import { loadCronJobsStoreSync, resolveCronJobsStorePath } from "../cron/store.js";
@@ -118,7 +119,7 @@ export function readLastAssistantFromSessionFile(filePath: string | undefined):
   }
   for (let index = lines.length - 1; index >= 0; index -= 1) {
     try {
-      const parsed = JSON.parse(lines[index]) as {
+      const parsed = JSON.parse(expectDefined(lines[index], "lines entry at index")) as {
         message?: { role?: unknown; content?: unknown };
       };
       if (parsed.message?.role !== "assistant") {
diff --git a/src/logging/diagnostic-stability-bundle.ts b/src/logging/diagnostic-stability-bundle.ts
index 33577b9a49b6..94b5c01ab4da 100644
--- a/src/logging/diagnostic-stability-bundle.ts
+++ b/src/logging/diagnostic-stability-bundle.ts
@@ -3,6 +3,7 @@ import fs from "node:fs";
 import path from "node:path";
 import process from "node:process";
 import v8 from "node:v8";
+import { expectDefined } from "@openclaw/normalization-core";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { resolveStateDir } from "../config/paths.js";
 import type {
@@ -1027,10 +1028,10 @@ function collectActiveResources(): DiagnosticActiveResourceSummary | undefined {
 function sanitizeSessionEvidencePath(relativePath: string): string {
   const parts = relativePath.split("/");
   if (parts.length === 4 && parts[0] === "agents" && parts[2] === "sessions") {
-    return `agents/<agent>/sessions/${sanitizeSessionEvidenceFileName(parts[3])}`;
+    return `agents/<agent>/sessions/${sanitizeSessionEvidenceFileName(expectDefined(parts[3], "parts entry at 3"))}`;
   }
   if (parts.length === 2 && parts[0] === "sessions") {
-    return `sessions/${sanitizeSessionEvidenceFileName(parts[1])}`;
+    return `sessions/${sanitizeSessionEvidenceFileName(expectDefined(parts[1], "parts entry at 1"))}`;
   }
   return redactSensitiveText(relativePath, { mode: "tools" });
 }
diff --git a/src/logging/logger.ts b/src/logging/logger.ts
index 099105bc8acf..2be688fe7756 100644
--- a/src/logging/logger.ts
+++ b/src/logging/logger.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { Logger as TsLogger } from "tslog";
 import type { OpenClawConfig } from "../config/types.js";
@@ -607,7 +608,10 @@ function buildLogger(settings: ResolvedSettings): TsLogger<LogObj> {
       const structuredFields = buildStructuredFileLogFields(logObj as TsLogRecord);
       const record = {
         ...logObj,
-        _meta: withResolvedLogMetaHostname(logObj["_meta"], structuredFields.hostname),
+        _meta: withResolvedLogMetaHostname(
+          logObj["_meta"],
+          expectDefined(structuredFields.hostname, "structured log hostname"),
+        ),
         time,
         ...structuredFields,
         ...traceFields,
diff --git a/src/logging/redact.ts b/src/logging/redact.ts
index 93c7f5fbad42..b584753790c0 100644
--- a/src/logging/redact.ts
+++ b/src/logging/redact.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Redaction helpers scrub secrets and sensitive identifiers from log output.
 import { sliceUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
@@ -317,8 +318,11 @@ function parsePattern(raw: RedactPattern): RegExp | null {
   } else if (raw.trim()) {
     const match = raw.match(/^\/(.+)\/([gimsuy]*)$/);
     if (match) {
-      const flags = match[2].includes("g") ? match[2] : `${match[2]}g`;
-      pattern = compileConfigRegex(match[1], flags)?.regex ?? null;
+      const flags = expectDefined(match[2], "redact regex capture 2").includes("g")
+        ? match[2]
+        : `${match[2]}g`;
+      pattern =
+        compileConfigRegex(expectDefined(match[1], "redact regex capture 1"), flags)?.regex ?? null;
     } else {
       pattern = compileConfigRegex(raw, "gi")?.regex ?? null;
     }
diff --git a/src/logging/secret-redaction-registry.ts b/src/logging/secret-redaction-registry.ts
index 8aff64adb56f..dc95f67fb7b5 100644
--- a/src/logging/secret-redaction-registry.ts
+++ b/src/logging/secret-redaction-registry.ts
@@ -10,7 +10,7 @@ function escapeRegExp(value: string): string {
 }
 
 function rebuildProbe(): void {
-  firstChars = new Set([...registeredValues.keys()].map((value) => value[0]));
+  firstChars = new Set([...registeredValues.keys()].map((value) => value.charAt(0)));
   compiledMatcher = undefined;
 }
 
diff --git a/src/logging/subsystem.ts b/src/logging/subsystem.ts
index dd1f651ae68f..5cb2c1ba2c69 100644
--- a/src/logging/subsystem.ts
+++ b/src/logging/subsystem.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Subsystem logger helpers create scoped loggers with subsystem-specific filters.
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { Chalk } from "chalk";
@@ -161,24 +162,29 @@ function pickSubsystemColor(color: ChalkInstance, subsystem: string): ChalkInsta
     hash = (hash * 31 + subsystem.charCodeAt(i)) | 0;
   }
   const idx = Math.abs(hash) % SUBSYSTEM_COLORS.length;
-  const name = SUBSYSTEM_COLORS[idx];
+  const name = expectDefined(SUBSYSTEM_COLORS[idx], "subsystem colors entry at idx");
   return color[name];
 }
 
 function formatSubsystemForConsole(subsystem: string): string {
   const parts = subsystem.split("/").filter(Boolean);
   const original = parts.join("/") || subsystem;
-  while (
-    parts.length > 0 &&
-    SUBSYSTEM_PREFIXES_TO_DROP.includes(parts[0] as (typeof SUBSYSTEM_PREFIXES_TO_DROP)[number])
-  ) {
+  while (parts.length > 0) {
+    const first = parts.at(0);
+    if (
+      first === undefined ||
+      !SUBSYSTEM_PREFIXES_TO_DROP.includes(first as (typeof SUBSYSTEM_PREFIXES_TO_DROP)[number])
+    ) {
+      break;
+    }
     parts.shift();
   }
-  if (parts.length === 0) {
+  const first = parts.at(0);
+  if (first === undefined) {
     return original;
   }
-  if (isChannelSubsystemPrefix(parts[0])) {
-    return parts[0];
+  if (isChannelSubsystemPrefix(first)) {
+    return first;
   }
   if (parts.length > SUBSYSTEM_MAX_SEGMENTS) {
     return parts.slice(-SUBSYSTEM_MAX_SEGMENTS).join("/");
diff --git a/src/media-understanding/apply.ts b/src/media-understanding/apply.ts
index 11c10cd83f7e..4d5f1fd020c1 100644
--- a/src/media-understanding/apply.ts
+++ b/src/media-understanding/apply.ts
@@ -1,6 +1,7 @@
 // Applies media-understanding outputs to inbound message context, including
 // attachment normalization, provider execution, file text extraction, and echoing.
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeLowercaseStringOrEmpty,
   normalizeOptionalString,
@@ -267,7 +268,9 @@ function hasSuspiciousBinarySignal(buffer?: Buffer): boolean {
   if (sample.length < 4 || sample[0] !== 0x50 || sample[1] !== 0x4b) {
     return false;
   }
-  const signature = (sample[2] << 8) | sample[3];
+  const signature =
+    (expectDefined(sample[2], "sample entry at 2") << 8) |
+    expectDefined(sample[3], "sample entry at 3");
   // Cover the ZIP local-header, central-directory, and empty-archive markers
   // so archive payloads cannot slip past text coercion when MIME detection is weak.
   return signature === 0x0304 || signature === 0x0102 || signature === 0x0506;
@@ -282,8 +285,8 @@ function decodeTextSample(buffer?: Buffer): string {
   if (utf16Charset === "utf-16be") {
     const swapped = Buffer.alloc(sample.length);
     for (let i = 0; i + 1 < sample.length; i += 2) {
-      swapped[i] = sample[i + 1];
-      swapped[i + 1] = sample[i];
+      swapped[i] = expectDefined(sample[i + 1], "UTF-16BE low byte");
+      swapped[i + 1] = expectDefined(sample[i], "UTF-16BE high byte");
     }
     return new TextDecoder("utf-16le").decode(swapped);
   }
diff --git a/src/media-understanding/runner.entries.ts b/src/media-understanding/runner.entries.ts
index c941897ac9e2..20b12a1d6438 100644
--- a/src/media-understanding/runner.entries.ts
+++ b/src/media-understanding/runner.entries.ts
@@ -2,6 +2,7 @@
 // rotation, output extraction, and decision summaries.
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeLowercaseStringOrEmpty,
   normalizeNullableString,
@@ -1072,11 +1073,15 @@ export async function runCliEntry(params: {
     if (shouldLogVerbose()) {
       logVerbose(`Media understanding via CLI: ${argv.join(" ")}`);
     }
-    const { stdout, stderr } = await runExec(argv[0], argv.slice(1), {
-      timeoutMs,
-      maxBuffer: CLI_OUTPUT_MAX_BUFFER,
-      cwd: isAntigravityCliCommand(command) ? path.dirname(mediaPath) : undefined,
-    });
+    const { stdout, stderr } = await runExec(
+      expectDefined(argv[0], "argv entry at 0"),
+      argv.slice(1),
+      {
+        timeoutMs,
+        maxBuffer: CLI_OUTPUT_MAX_BUFFER,
+        cwd: isAntigravityCliCommand(command) ? path.dirname(mediaPath) : undefined,
+      },
+    );
     const requestedBackend =
       capability === "audio"
         ? resolveRequestedLocalAudioBackend({
diff --git a/src/media/fetch.ts b/src/media/fetch.ts
index 59bd47c94653..f592e6754b9e 100644
--- a/src/media/fetch.ts
+++ b/src/media/fetch.ts
@@ -3,6 +3,7 @@ import { MAX_DOCUMENT_BYTES } from "@openclaw/media-core/constants";
 import { parseMediaContentLength } from "@openclaw/media-core/content-length";
 import { basenameFromAnyPath, extnameFromAnyPath } from "@openclaw/media-core/file-name";
 import { detectMime, extensionForMime } from "@openclaw/media-core/mime";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isAbortError, mergeAbortSignals } from "../infra/abort-signal.js";
 import { formatErrorMessage } from "../infra/errors.js";
 import {
@@ -237,7 +238,7 @@ async function fetchGuardedMediaResponse(
     const attemptErrors: unknown[] = [];
     for (let i = 0; i < attempts.length; i += 1) {
       try {
-        result = await runGuardedFetch(attempts[i]);
+        result = await runGuardedFetch(expectDefined(attempts[i], "attempts entry at i"));
         break;
       } catch (err) {
         if (
diff --git a/src/media/parse.ts b/src/media/parse.ts
index 4b0332f81078..9c320d6f75ce 100644
--- a/src/media/parse.ts
+++ b/src/media/parse.ts
@@ -10,6 +10,7 @@ import {
   parseLooseIpAddress,
 } from "@openclaw/net-policy/ip";
 import { hasHttpUrlPrefix } from "@openclaw/net-policy/url-protocol";
+import { expectDefined } from "@openclaw/normalization-core";
 import { parseFenceSpans } from "../../packages/markdown-core/src/fences.js";
 import { parseAudioTag } from "./audio-tags.js";
 
@@ -346,7 +347,7 @@ function parseMarkdownImageDestination(
   let destinationEnd = index;
   let parenDepth = 0;
   while (index < input.length) {
-    const ch = input[index];
+    const ch = input.charAt(index);
     if (ch === "\\") {
       index += 2;
       destinationEnd = index;
@@ -583,7 +584,7 @@ export function splitMediaFromOutput(
       const start = match.index ?? 0;
       pieces.push(line.slice(cursor, start));
 
-      const payload = match[1];
+      const payload = expectDefined(match[1], "parse regex capture 1");
       const unwrapped = unwrapQuoted(payload);
       const payloadValue = unwrapped ?? payload;
       const parts = unwrapped ? [unwrapped] : payload.split(/\s+/).filter(Boolean);
diff --git a/src/media/png-encode.ts b/src/media/png-encode.ts
index eff04189c8cb..a35ab5e46ef8 100644
--- a/src/media/png-encode.ts
+++ b/src/media/png-encode.ts
@@ -1,5 +1,6 @@
 // PNG encode helpers build small PNG files without external image dependencies.
 import { deflateSync } from "node:zlib";
+import { expectDefined } from "@openclaw/normalization-core";
 
 const CRC_TABLE = (() => {
   const table = new Uint32Array(256);
@@ -17,7 +18,9 @@ const CRC_TABLE = (() => {
 function crc32(buf: Buffer): number {
   let crc = 0xffffffff;
   for (const byte of buf) {
-    crc = CRC_TABLE[(crc ^ byte) & 0xff] ^ (crc >>> 8);
+    crc =
+      expectDefined(CRC_TABLE[(crc ^ byte) & 0xff], "crc table entry at (crc ^ byte) & 0xff") ^
+      (crc >>> 8);
   }
   return (crc ^ 0xffffffff) >>> 0;
 }
diff --git a/src/node-host/invoke-system-run-allowlist.ts b/src/node-host/invoke-system-run-allowlist.ts
index 3cccade374c2..e6ca0497272f 100644
--- a/src/node-host/invoke-system-run-allowlist.ts
+++ b/src/node-host/invoke-system-run-allowlist.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Resolves system.run allowlist matches, argv plans, and truncated command output. */
 import {
   analyzeArgvCommand,
@@ -132,7 +133,9 @@ export function resolvePlannedAllowlistArgv(params: {
   ) {
     return undefined;
   }
-  const plannedAllowlistArgv = resolvePlannedSegmentArgv(params.segments[0]);
+  const plannedAllowlistArgv = resolvePlannedSegmentArgv(
+    expectDefined(params.segments[0], "segments entry at 0"),
+  );
   return plannedAllowlistArgv && plannedAllowlistArgv.length > 0 ? plannedAllowlistArgv : null;
 }
 
@@ -172,7 +175,9 @@ export async function resolveSystemRunExecArgv(params: {
   ) {
     // Exact-path matches stay bound to the resolved executable, while the bare
     // wildcard contract can still authorize unresolved Windows commands.
-    const plannedArgv = resolvePlannedSegmentArgv(params.segments[0]);
+    const plannedArgv = resolvePlannedSegmentArgv(
+      expectDefined(params.segments[0], "segments entry at 0"),
+    );
     if (!plannedArgv) {
       return null;
     }
diff --git a/src/node-host/invoke-system-run-plan.ts b/src/node-host/invoke-system-run-plan.ts
index 9d3b0c87d4bf..c4c814a7758d 100644
--- a/src/node-host/invoke-system-run-plan.ts
+++ b/src/node-host/invoke-system-run-plan.ts
@@ -2,6 +2,7 @@
 import crypto from "node:crypto";
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import {
   normalizeLowercaseStringOrEmpty,
   normalizeNullableString,
@@ -562,7 +563,7 @@ function resolveGenericInterpreterScriptOperandIndex(params: {
   if (collection.sawOptionValueFile) {
     return null;
   }
-  return collection.hits.length === 1 ? collection.hits[0] : null;
+  return collection.hits.length === 1 ? expectDefined(collection.hits[0], "hits entry at 0") : null;
 }
 
 function resolveBunScriptOperandIndex(params: {
diff --git a/src/node-host/invoke.ts b/src/node-host/invoke.ts
index 15140f6a0ce0..d4882e712f79 100644
--- a/src/node-host/invoke.ts
+++ b/src/node-host/invoke.ts
@@ -3,6 +3,7 @@ import { spawn } from "node:child_process";
 import fs from "node:fs";
 import path from "node:path";
 import type { ContentBlock } from "@modelcontextprotocol/sdk/types.js";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { normalizeStringEntries } from "@openclaw/normalization-core/string-normalization";
 import { sliceUtf16Safe, truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
@@ -355,7 +356,7 @@ async function runCommand(
     // node result because runner.ts intentionally dispatches invokes with `void`.
     let child: ReturnType<typeof spawn>;
     try {
-      child = spawn(argv[0], argv.slice(1), {
+      child = spawn(expectDefined(argv[0], "argv entry at 0"), argv.slice(1), {
         cwd,
         env,
         stdio: ["ignore", "pipe", "pipe"],
diff --git a/src/pairing/pairing-store.ts b/src/pairing/pairing-store.ts
index 72af4d2fd55c..56fb963d9a37 100644
--- a/src/pairing/pairing-store.ts
+++ b/src/pairing/pairing-store.ts
@@ -209,26 +209,26 @@ function pruneExcessRequestsByAccount(reqs: PairingRequest[], maxPending: number
   if (maxPending <= 0 || reqs.length <= maxPending) {
     return { requests: reqs, removed: false };
   }
-  const grouped = new Map<string, number[]>();
+  const grouped = new Map<string, Array<{ index: number; request: PairingRequest }>>();
   for (const [index, entry] of reqs.entries()) {
     const accountId = resolvePairingRequestAccountId(entry);
     const current = grouped.get(accountId);
     if (current) {
-      current.push(index);
+      current.push({ index, request: entry });
       continue;
     }
-    grouped.set(accountId, [index]);
+    grouped.set(accountId, [{ index, request: entry }]);
   }
 
   const droppedIndexes = new Set<number>();
-  for (const indexes of grouped.values()) {
-    if (indexes.length <= maxPending) {
+  for (const entries of grouped.values()) {
+    if (entries.length <= maxPending) {
       continue;
     }
-    const sortedIndexes = indexes
-      .slice()
-      .toSorted((left, right) => resolveLastSeenAt(reqs[left]) - resolveLastSeenAt(reqs[right]));
-    for (const index of sortedIndexes.slice(0, sortedIndexes.length - maxPending)) {
+    const sortedEntries = entries.toSorted(
+      (left, right) => resolveLastSeenAt(left.request) - resolveLastSeenAt(right.request),
+    );
+    for (const { index } of sortedEntries.slice(0, sortedEntries.length - maxPending)) {
       droppedIndexes.add(index);
     }
   }
diff --git a/src/plugin-sdk/allowlist-config-edit.ts b/src/plugin-sdk/allowlist-config-edit.ts
index d798d30843f9..d082c800284f 100644
--- a/src/plugin-sdk/allowlist-config-edit.ts
+++ b/src/plugin-sdk/allowlist-config-edit.ts
@@ -5,6 +5,7 @@ import type { ChannelId } from "../channels/plugins/types.public.js";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
 import { isBlockedObjectKey } from "../infra/prototype-keys.js";
 import { DEFAULT_ACCOUNT_ID, normalizeAccountId } from "../routing/session-key.js";
+import { isRecord } from "../utils.js";
 
 type AllowlistConfigPaths = {
   readPaths: string[][];
@@ -234,30 +235,32 @@ function ensureNestedObject(
 }
 
 function setNestedValue(root: Record<string, unknown>, path: string[], value: unknown) {
-  if (path.length === 0) {
+  const leaf = path.at(-1);
+  if (leaf === undefined) {
     return;
   }
   if (path.length === 1) {
-    root[path[0]] = value;
+    root[leaf] = value;
     return;
   }
   const parent = ensureNestedObject(root, path.slice(0, -1));
-  parent[path[path.length - 1]] = value;
+  parent[leaf] = value;
 }
 
 function deleteNestedValue(root: Record<string, unknown>, path: string[]) {
-  if (path.length === 0) {
+  const leaf = path.at(-1);
+  if (leaf === undefined) {
     return;
   }
   if (path.length === 1) {
-    delete root[path[0]];
+    delete root[leaf];
     return;
   }
   const parent = getNestedValue(root, path.slice(0, -1));
-  if (!parent || typeof parent !== "object") {
+  if (!isRecord(parent)) {
     return;
   }
-  delete (parent as Record<string, unknown>)[path[path.length - 1]];
+  delete parent[leaf];
 }
 
 function applyAccountScopedAllowlistConfigEdit(params: {
diff --git a/src/plugin-sdk/core.ts b/src/plugin-sdk/core.ts
index 79c754a6ba57..024e2a5bac6e 100644
--- a/src/plugin-sdk/core.ts
+++ b/src/plugin-sdk/core.ts
@@ -1,4 +1,5 @@
 // Core SDK contracts expose stable identifiers, manifests, and shared plugin metadata types.
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "../../packages/normalization-core/src/string-coerce.js";
 import type { ResolvedConfiguredAcpBinding } from "../acp/persistent-bindings.types.js";
 import { buildChatChannelMetaById } from "../channels/chat-meta-shared.js";
@@ -322,12 +323,14 @@ function resolveSdkChatChannelMeta(id: string) {
       metaById: buildChatChannelMetaById(),
     };
   }
+  // Optional by design: createChannelPluginBase serves external plugin ids that
+  // are never in the bundled catalog; their meta comes entirely from params.meta.
   return cachedSdkChatChannelMeta.metaById[id];
 }
 
 /** Resolve bundled chat channel metadata while respecting the active bundled-plugin directory. */
 export function getChatChannelMeta(id: ChatChannelId): ChannelMeta {
-  return resolveSdkChatChannelMeta(id);
+  return expectDefined(resolveSdkChatChannelMeta(id), `chat channel metadata: ${id}`);
 }
 
 /** Remove one of the known provider prefixes from a free-form target string. */
diff --git a/src/plugin-sdk/extension-shared.ts b/src/plugin-sdk/extension-shared.ts
index 7c852510dc6f..bb523e806066 100644
--- a/src/plugin-sdk/extension-shared.ts
+++ b/src/plugin-sdk/extension-shared.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Extension shared helpers expose cross-plugin runtime utilities that remain SDK-safe.
 import { createAmbientNodeProxyAgent, hasAmbientNodeProxyConfigured } from "@openclaw/proxyline";
 import type { z } from "zod";
@@ -183,7 +184,10 @@ export function formatPluginConfigIssue(
     return options?.invalidConfigMessage ?? "invalid config";
   }
   if (issue.code === "unrecognized_keys" && issue.keys.length > 0) {
-    return options?.unknownKeyMessage?.(issue.keys[0]) ?? `unknown config key: ${issue.keys[0]}`;
+    return (
+      options?.unknownKeyMessage?.(expectDefined(issue.keys[0], "keys entry at 0")) ??
+      `unknown config key: ${issue.keys[0]}`
+    );
   }
   if (issue.code === "invalid_type" && issue.path.length === 0) {
     return options?.rootInvalidTypeMessage ?? "expected config object";
diff --git a/src/plugin-sdk/reply-payload.ts b/src/plugin-sdk/reply-payload.ts
index 024b39a626e3..df9f077196ac 100644
--- a/src/plugin-sdk/reply-payload.ts
+++ b/src/plugin-sdk/reply-payload.ts
@@ -235,20 +235,21 @@ export async function sendPayloadWithChunkedTextAndMedia<
   if (!text && urls.length === 0) {
     return params.emptyResult;
   }
-  if (urls.length > 0) {
+  const [firstUrl, ...remainingUrls] = urls;
+  if (firstUrl !== undefined) {
     // Caption-limited transports get text only on the first media item; the
     // final result still represents the last platform send.
     let lastResult = await params.sendMedia({
       ...params.ctx,
       text,
-      mediaUrl: urls[0],
+      mediaUrl: firstUrl,
     });
     await params.onResult?.(lastResult);
-    for (let i = 1; i < urls.length; i++) {
+    for (const mediaUrl of remainingUrls) {
       lastResult = await params.sendMedia({
         ...params.ctx,
         text: "",
-        mediaUrl: urls[i],
+        mediaUrl,
       });
       await params.onResult?.(lastResult);
     }
@@ -256,12 +257,17 @@ export async function sendPayloadWithChunkedTextAndMedia<
   }
   const limit = params.textChunkLimit;
   const chunks = limit && params.chunker ? params.chunker(text, limit) : [text];
-  let lastResult: TResult;
-  for (const chunk of chunks) {
+  const [firstChunk, ...remainingChunks] = chunks;
+  if (firstChunk === undefined) {
+    return params.emptyResult;
+  }
+  let lastResult = await params.sendText({ ...params.ctx, text: firstChunk });
+  await params.onResult?.(lastResult);
+  for (const chunk of remainingChunks) {
     lastResult = await params.sendText({ ...params.ctx, text: chunk });
     await params.onResult?.(lastResult);
   }
-  return lastResult!;
+  return lastResult;
 }
 
 /** Sends a media sequence with caption text on the first item and returns the last send result. */
diff --git a/src/plugin-sdk/session-transcript-hit.ts b/src/plugin-sdk/session-transcript-hit.ts
index 3903ac824b8b..2b943cc51c6a 100644
--- a/src/plugin-sdk/session-transcript-hit.ts
+++ b/src/plugin-sdk/session-transcript-hit.ts
@@ -1,5 +1,6 @@
 // Session transcript hit helpers describe and load matched transcript snippets for plugins.
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "../../packages/normalization-core/src/string-coerce.js";
 import { uniqueStrings } from "../../packages/normalization-core/src/string-normalization.js";
 import { parseUsageCountedSessionIdFromFileName } from "../config/sessions/artifacts.js";
@@ -40,7 +41,9 @@ function restoreQmdNormalizedArchiveName(mdStem: string): string | null {
     return null;
   }
   const [, sessionId, reason, timestamp] = match;
-  const restoredTimestamp = restoreQmdNormalizedArchiveTimestamp(timestamp);
+  const restoredTimestamp = restoreQmdNormalizedArchiveTimestamp(
+    expectDefined(timestamp, "session transcript hit timestamp"),
+  );
   return restoredTimestamp ? `${sessionId}.jsonl.${reason}.${restoredTimestamp}` : null;
 }
 
diff --git a/src/plugin-sdk/test-helpers/image-fixtures.ts b/src/plugin-sdk/test-helpers/image-fixtures.ts
index 4584a9f75e26..232fc94129c0 100644
--- a/src/plugin-sdk/test-helpers/image-fixtures.ts
+++ b/src/plugin-sdk/test-helpers/image-fixtures.ts
@@ -1,5 +1,6 @@
 // Deterministic image buffers for plugin SDK media tests.
 import { deflateSync } from "node:zlib";
+import { expectDefined } from "@openclaw/normalization-core";
 import { encodePngRgb, encodePngRgba } from "../../media/png-encode.js";
 
 type Rgba = {
@@ -30,7 +31,9 @@ const CRC_TABLE = (() => {
 function crc32(buffer: Buffer): number {
   let crc = 0xffffffff;
   for (const byte of buffer) {
-    crc = CRC_TABLE[(crc ^ byte) & 0xff] ^ (crc >>> 8);
+    crc =
+      expectDefined(CRC_TABLE[(crc ^ byte) & 0xff], "crc table entry at (crc ^ byte) & 0xff") ^
+      (crc >>> 8);
   }
   return (crc ^ 0xffffffff) >>> 0;
 }
diff --git a/src/plugin-sdk/test-helpers/temp-home.ts b/src/plugin-sdk/test-helpers/temp-home.ts
index 06efeca3b969..e7918eab1f74 100644
--- a/src/plugin-sdk/test-helpers/temp-home.ts
+++ b/src/plugin-sdk/test-helpers/temp-home.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { deleteTestEnvValue, setTestEnvValue } from "../../test-utils/env.js";
 import { cleanupSessionStateForTest } from "../../test-utils/session-state-cleanup.js";
 
@@ -82,7 +83,7 @@ function setTempHome(base: string) {
   if (!match) {
     return;
   }
-  setTestEnvValue("HOMEDRIVE", match[1]);
+  setTestEnvValue("HOMEDRIVE", expectDefined(match[1], "temp home regex capture 1"));
   setTestEnvValue("HOMEPATH", match[2] || "\\");
 }
 
diff --git a/src/plugin-state/plugin-state-store.sqlite.ts b/src/plugin-state/plugin-state-store.sqlite.ts
index e106d783c0ce..3923f81669a1 100644
--- a/src/plugin-state/plugin-state-store.sqlite.ts
+++ b/src/plugin-state/plugin-state-store.sqlite.ts
@@ -898,8 +898,7 @@ export function seedPluginStateDatabaseEntriesForTests(
 
   const now = Date.now();
   runWriteTransaction("register", (store) => {
-    for (let index = 0; index < entries.length; index += 1) {
-      const entry = entries[index];
+    for (const [index, entry] of entries.entries()) {
       upsertPluginStateEntry(
         store.db,
         bindPluginStateEntry({
diff --git a/src/plugins/contracts/inventory/bundled-capability-metadata.ts b/src/plugins/contracts/inventory/bundled-capability-metadata.ts
index 930efa7e86c4..f4688b381f76 100644
--- a/src/plugins/contracts/inventory/bundled-capability-metadata.ts
+++ b/src/plugins/contracts/inventory/bundled-capability-metadata.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
+import { expectDefined } from "@openclaw/normalization-core";
 import { tryReadJsonSync } from "../../../infra/json-files.js";
 import {
   normalizeBundledPluginStringList,
@@ -224,7 +225,11 @@ export const BUNDLED_AUTO_ENABLE_PROVIDER_PLUGIN_IDS = Object.fromEntries(
       providerId,
       manifest.id,
     ]),
-  ).toSorted(([left], [right]) => left.localeCompare(right)),
+  ).toSorted(([left], [right]) =>
+    expectDefined(left, "bundled capability metadata left").localeCompare(
+      expectDefined(right, "bundled capability metadata right"),
+    ),
+  ),
 ) as Readonly<Record<string, string>>;
 
 type BundledContractIdSnapshotKey = Exclude<
diff --git a/src/plugins/contracts/registry.ts b/src/plugins/contracts/registry.ts
index 69624accda99..d7006eee9c53 100644
--- a/src/plugins/contracts/registry.ts
+++ b/src/plugins/contracts/registry.ts
@@ -1,5 +1,6 @@
 // Plugin contract registry assembles bundled plugin fixtures for shared contract tests.
 import { normalizeProviderId } from "@openclaw/model-catalog-core/provider-id";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { loadBundledCapabilityRuntimeRegistry } from "../bundled-capability-runtime.js";
 import { discoverOpenClawPlugins } from "../discovery.js";
@@ -383,7 +384,7 @@ export function requireProviderContractProvider(providerId: string): ProviderPlu
       ...new Map(entries.map((entry) => [entry.provider.id, entry.provider])).values(),
     ];
     if (pluginIds.length === 1 && pluginScopedProviders.length === 1) {
-      return pluginScopedProviders[0];
+      return expectDefined(pluginScopedProviders[0], "plugin scoped providers entry at 0");
     }
     if (providerContractLoadError) {
       throw new Error(
diff --git a/src/plugins/dependency-denylist.ts b/src/plugins/dependency-denylist.ts
index 9026c28cd37a..6a8b5f919890 100644
--- a/src/plugins/dependency-denylist.ts
+++ b/src/plugins/dependency-denylist.ts
@@ -172,7 +172,9 @@ function collectBlockedOverrideFindings(
   }
 
   const findings: BlockedManifestDependencyFinding[] = [];
-  for (const overrideKey of Object.keys(value).toSorted()) {
+  for (const [overrideKey, overrideValue] of Object.entries(value).toSorted(([left], [right]) =>
+    left.localeCompare(right),
+  )) {
     const overrideSelectorPackageName = parsePackageNameFromOverrideSelector(overrideKey);
     if (
       overrideSelectorPackageName &&
@@ -184,7 +186,7 @@ function collectBlockedOverrideFindings(
         field: "overrides",
       });
     }
-    findings.push(...collectBlockedOverrideFindings(value[overrideKey], [...path, overrideKey]));
+    findings.push(...collectBlockedOverrideFindings(overrideValue, [...path, overrideKey]));
   }
   return findings;
 }
@@ -209,13 +211,15 @@ export function findBlockedManifestDependencies(
     if (!dependencyMap) {
       continue;
     }
-    for (const dependencyName of Object.keys(dependencyMap).toSorted()) {
+    for (const [dependencyName, dependencySpec] of Object.entries(dependencyMap).toSorted(
+      ([left], [right]) => left.localeCompare(right),
+    )) {
       if (isBlockedInstallDependencyPackageName(dependencyName)) {
         findings.push({ dependencyName, field });
         continue;
       }
 
-      const aliasTargetPackageName = parseNpmAliasTargetPackageName(dependencyMap[dependencyName]);
+      const aliasTargetPackageName = parseNpmAliasTargetPackageName(dependencySpec);
       if (!aliasTargetPackageName) {
         continue;
       }
diff --git a/src/plugins/hook-runner-global-state.ts b/src/plugins/hook-runner-global-state.ts
index 403f67e7e9d9..5c61c5f302da 100644
--- a/src/plugins/hook-runner-global-state.ts
+++ b/src/plugins/hook-runner-global-state.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Internal state and composed-registry view for the global hook runner.
 import { resolveGlobalSingleton } from "../shared/global-singleton.js";
 import type { GlobalHookRunnerRegistry } from "./hook-registry.types.js";
@@ -89,7 +90,12 @@ function composeLiveHookRegistry(
   // registration that still carries a fail-closed tool-call gate.
   sources.forEach((registry, index) => {
     for (const plugin of registry.plugins) {
-      if (plugin.status === "loaded" && hookPluginIdsBySource[index].has(plugin.id)) {
+      if (
+        plugin.status === "loaded" &&
+        expectDefined(hookPluginIdsBySource[index], "hook plugin ids by source entry at index").has(
+          plugin.id,
+        )
+      ) {
         claimOwner(plugin.id, index);
       }
     }
@@ -133,7 +139,13 @@ function composeLiveHookRegistry(
   });
   sources.forEach((registry, index) => {
     for (const plugin of registry.plugins) {
-      if (plugin.status === "loaded" && trustedPolicyPluginIdsBySource[index].has(plugin.id)) {
+      if (
+        plugin.status === "loaded" &&
+        expectDefined(
+          trustedPolicyPluginIdsBySource[index],
+          "trusted policy plugin ids by source entry at index",
+        ).has(plugin.id)
+      ) {
         claimPolicyOwner(plugin.id, index);
       }
     }
diff --git a/src/plugins/installs.ts b/src/plugins/installs.ts
index 73a4f7bb934a..89f88b5bde9c 100644
--- a/src/plugins/installs.ts
+++ b/src/plugins/installs.ts
@@ -52,22 +52,20 @@ export function recordPluginInstall(
 ): OpenClawConfig {
   const { pluginId, ...record } = update;
   const previous = clearStaleInstallRecordFields(cfg.plugins?.installs?.[pluginId]);
-  const installs = {
-    ...cfg.plugins?.installs,
-    [pluginId]: {
-      ...previous,
-      ...record,
-      installedAt: record.installedAt ?? new Date().toISOString(),
-    },
+  const nextRecord = {
+    ...previous,
+    ...record,
+    installedAt: record.installedAt ?? new Date().toISOString(),
   };
 
   return {
     ...cfg,
     plugins: {
+      // cfg.plugins may be absent on first install; spreading undefined is {}.
       ...cfg.plugins,
       installs: {
-        ...installs,
-        [pluginId]: installs[pluginId],
+        ...cfg.plugins?.installs,
+        [pluginId]: nextRecord,
       },
     },
   };
diff --git a/src/plugins/plugin-registry-snapshot.ts b/src/plugins/plugin-registry-snapshot.ts
index eecff840a1d2..ed40a0d34a76 100644
--- a/src/plugins/plugin-registry-snapshot.ts
+++ b/src/plugins/plugin-registry-snapshot.ts
@@ -2,6 +2,7 @@
 import crypto from "node:crypto";
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { tryReadJsonSync } from "../infra/json-files.js";
 import { resolveUserPath } from "../utils.js";
 import { resolveCompatibilityHostVersion } from "../version.js";
@@ -203,7 +204,11 @@ function directoryChildFingerprint(directoryPath: string): unknown {
     return fs
       .readdirSync(directoryPath, { withFileTypes: true })
       .map((entry) => [entry.name, entry.isDirectory() ? "dir" : entry.isFile() ? "file" : "other"])
-      .toSorted(([left], [right]) => left.localeCompare(right));
+      .toSorted(([left], [right]) =>
+        expectDefined(left, "plugin registry snapshot left").localeCompare(
+          expectDefined(right, "plugin registry snapshot right"),
+        ),
+      );
   } catch {
     return "unreadable";
   }
diff --git a/src/plugins/provider-auth-input.ts b/src/plugins/provider-auth-input.ts
index 706d8d59d51e..8578c5363c8d 100644
--- a/src/plugins/provider-auth-input.ts
+++ b/src/plugins/provider-auth-input.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Normalizes provider auth input metadata collected from plugin setup flows. */
 import {
   normalizeOptionalLowercaseString,
@@ -41,7 +42,9 @@ export function normalizeApiKeyInput(raw: string): string {
   const assignmentMatch = normalizedPaste.match(
     /^(?:export\s+)?[A-Za-z_][A-Za-z0-9_]*\s*=\s*(.+)$/,
   );
-  const valuePart = assignmentMatch ? assignmentMatch[1].trim() : normalizedPaste;
+  const valuePart = assignmentMatch
+    ? expectDefined(assignmentMatch[1], "assignment match capture group 1").trim()
+    : normalizedPaste;
   const withoutSemicolon = valuePart.endsWith(";") ? valuePart.slice(0, -1).trim() : valuePart;
 
   const unquoted =
diff --git a/src/plugins/provider-wizard.ts b/src/plugins/provider-wizard.ts
index 1189a09e57e0..7383f5925866 100644
--- a/src/plugins/provider-wizard.ts
+++ b/src/plugins/provider-wizard.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /** Provider setup wizard helpers shared by provider plugins and CLI setup flows. */
 import {
   normalizeOptionalLowercaseString,
@@ -290,7 +291,10 @@ export function resolveProviderPluginChoice(params: {
       normalizeProviderId(provider.id) === normalizeProviderId(choice) &&
       provider.auth.length > 0
     ) {
-      return { provider, method: provider.auth[0] };
+      return {
+        provider,
+        method: expectDefined(provider.auth[0], "auth entry at 0"),
+      };
     }
   }
 
diff --git a/src/plugins/runtime/runtime-plugin-boundary.ts b/src/plugins/runtime/runtime-plugin-boundary.ts
index eee78779d318..4c6c74e7342a 100644
--- a/src/plugins/runtime/runtime-plugin-boundary.ts
+++ b/src/plugins/runtime/runtime-plugin-boundary.ts
@@ -1,6 +1,7 @@
 // Runtime plugin boundary helpers enforce package and source boundaries for runtime loading.
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { getRuntimeConfig } from "../../config/config.js";
 import { loadPluginManifestRegistry } from "../manifest-registry.js";
 import {
@@ -79,7 +80,7 @@ export function resolvePluginRuntimeRecordByEntryBaseNames(
       `plugin runtime boundary is ambiguous for entries [${entryBaseNames.join(", ")}]: ${pluginIds}`,
     );
   }
-  const record = matches[0];
+  const record = expectDefined(matches[0], "matches capture group 0");
   return {
     ...(record.origin ? { origin: record.origin } : {}),
     rootDir: record.rootDir,
diff --git a/src/poll-params.ts b/src/poll-params.ts
index 5b12f9fbb672..c3b315b20be8 100644
--- a/src/poll-params.ts
+++ b/src/poll-params.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Parses poll command parameters into validated polling options.
 import { readSnakeCaseParamRaw } from "./param-key.js";
 
@@ -37,7 +38,10 @@ const CONTENT_BEARING_SHARED_POLL_PARAM_NAMES = ["pollQuestion", "pollOption"] a
 
 function hasContentBearingPollCreationParam(params: Record<string, unknown>): boolean {
   for (const key of CONTENT_BEARING_SHARED_POLL_PARAM_NAMES) {
-    const def = POLL_CREATION_PARAM_DEFS[key];
+    const def = expectDefined(
+      POLL_CREATION_PARAM_DEFS[key],
+      "poll creation param defs entry at key",
+    );
     const value = readPollParamRaw(params, key);
     if (def.kind === "string" && typeof value === "string" && value.trim().length > 0) {
       return true;
diff --git a/src/process/exec.ts b/src/process/exec.ts
index 92bb371059be..10527732c3cf 100644
--- a/src/process/exec.ts
+++ b/src/process/exec.ts
@@ -5,6 +5,7 @@ import path from "node:path";
 import process from "node:process";
 import { StringDecoder } from "node:string_decoder";
 import { promisify } from "node:util";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { danger, shouldLogVerbose } from "../globals.js";
 import { markOpenClawExecEnv } from "../infra/openclaw-exec-env.js";
@@ -71,10 +72,9 @@ function resolveNpmArgvForWindows(argv: string[]): string[] | null {
   if (process.platform !== "win32" || argv.length === 0) {
     return null;
   }
-  const basename = normalizeLowercaseStringOrEmpty(path.basename(argv[0])).replace(
-    /\.(cmd|exe|bat)$/,
-    "",
-  );
+  const basename = normalizeLowercaseStringOrEmpty(
+    path.basename(expectDefined(argv[0], "argv entry at 0")),
+  ).replace(/\.(cmd|exe|bat)$/, "");
   const cliName = basename === "npx" ? "npx-cli.js" : basename === "npm" ? "npm-cli.js" : null;
   if (!cliName) {
     return null;
@@ -278,7 +278,7 @@ function appendCapturedOutput(
   capture.chunks.push(buffer);
   capture.bytes += buffer.byteLength;
   while (capture.bytes > maxBytes && capture.chunks.length > 0) {
-    const first = capture.chunks[0];
+    const first = expectDefined(capture.chunks[0], "chunks entry at 0");
     const overflow = capture.bytes - maxBytes;
     if (first.byteLength <= overflow) {
       capture.chunks.shift();
diff --git a/src/process/spawn-utils.ts b/src/process/spawn-utils.ts
index 6fa195fcf3bb..7d57d4c0bb57 100644
--- a/src/process/spawn-utils.ts
+++ b/src/process/spawn-utils.ts
@@ -1,6 +1,7 @@
 // Spawn utilities configure child processes and normalize spawned process handles.
 import type { ChildProcess, SpawnOptions } from "node:child_process";
 import { spawn } from "node:child_process";
+import { expectDefined } from "@openclaw/normalization-core";
 import { toErrorObject } from "../infra/errors.js";
 
 type SpawnFallback = {
@@ -44,7 +45,7 @@ async function spawnAndWaitForSpawn(
   argv: string[],
   options: SpawnOptions,
 ): Promise<ChildProcess> {
-  const child = spawnImpl(argv[0], argv.slice(1), options);
+  const child = spawnImpl(expectDefined(argv[0], "argv entry at 0"), argv.slice(1), options);
 
   return await new Promise((resolve, reject) => {
     let settled = false;
@@ -98,8 +99,7 @@ export async function spawnWithFallback(
   ];
 
   let lastError: unknown;
-  for (let index = 0; index < attempts.length; index += 1) {
-    const attempt = attempts[index];
+  for (const [index, attempt] of attempts.entries()) {
     try {
       const child = await spawnAndWaitForSpawn(spawnImpl, params.argv, attempt.options);
       return {
diff --git a/src/process/supervisor/supervisor.ts b/src/process/supervisor/supervisor.ts
index 984c3378b903..f8c57d165bec 100644
--- a/src/process/supervisor/supervisor.ts
+++ b/src/process/supervisor/supervisor.ts
@@ -1,6 +1,7 @@
 // Process supervisor manages long-running child and PTY process lifecycles.
 import crypto from "node:crypto";
 import { performance } from "node:perf_hooks";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { sliceUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { getShellConfig } from "../../agents/shell-utils.js";
@@ -87,7 +88,7 @@ function resolveElapsedTimeoutReason(params: {
     return null;
   }
   elapsedDeadlines.sort((a, b) => a.deadlineMs - b.deadlineMs);
-  return elapsedDeadlines[0].reason;
+  return expectDefined(elapsedDeadlines[0], "elapsed deadlines entry at 0").reason;
 }
 
 export function createProcessSupervisor(): ProcessSupervisor {
diff --git a/src/routing/bindings.ts b/src/routing/bindings.ts
index 2bec9e11f498..fb702ec040d8 100644
--- a/src/routing/bindings.ts
+++ b/src/routing/bindings.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Routing binding helpers resolve configured channel and agent route bindings.
 import { resolveDefaultAgentId } from "../agents/agent-scope.js";
 import { listRouteBindings } from "../config/bindings.js";
@@ -80,7 +81,7 @@ export function resolvePreferredAccountId(params: {
   boundAccounts: string[];
 }): string {
   if (params.boundAccounts.length > 0) {
-    return params.boundAccounts[0];
+    return expectDefined(params.boundAccounts[0], "bound accounts entry at 0");
   }
   return params.defaultAccountId;
 }
diff --git a/src/secrets/resolve.ts b/src/secrets/resolve.ts
index c350366ffd23..6930f02548cd 100644
--- a/src/secrets/resolve.ts
+++ b/src/secrets/resolve.ts
@@ -2,6 +2,7 @@
 import { spawn } from "node:child_process";
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { uniqueStrings } from "@openclaw/normalization-core/string-normalization";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
 import type {
@@ -624,7 +625,7 @@ function parseExecValues(params: {
     try {
       parsed = JSON.parse(trimmed) as unknown;
     } catch {
-      return { [params.ids[0]]: trimmed };
+      return { [expectDefined(params.ids[0], "ids entry at 0")]: trimmed };
     }
   } else {
     try {
@@ -640,7 +641,7 @@ function parseExecValues(params: {
 
   if (!isRecord(parsed)) {
     if (!params.jsonOnly && params.ids.length === 1 && typeof parsed === "string") {
-      return { [params.ids[0]]: parsed };
+      return { [expectDefined(params.ids[0], "ids entry at 0")]: parsed };
     }
     throw providerResolutionError({
       source: "exec",
@@ -952,7 +953,7 @@ export async function resolveSecretRefValues(
         });
       }
       const providerConfig = resolveConfiguredProvider({
-        ref: group.refs[0],
+        ref: expectDefined(group.refs[0], "refs entry at 0"),
         config: options.config,
         env: options.env ?? process.env,
         manifestRegistry: options.manifestRegistry,
diff --git a/src/secrets/runtime-web-tools.shared.ts b/src/secrets/runtime-web-tools.shared.ts
index 37d1fe324060..6ca87c4b1a6c 100644
--- a/src/secrets/runtime-web-tools.shared.ts
+++ b/src/secrets/runtime-web-tools.shared.ts
@@ -12,6 +12,7 @@ import type {
 import { pushInactiveSurfaceWarning, pushWarning } from "./runtime-shared.js";
 import type { RuntimeWebDiagnostic, RuntimeWebDiagnosticCode } from "./runtime-web-tools.types.js";
 export { isRecord } from "./shared.js";
+import { expectDefined } from "@openclaw/normalization-core";
 import { isRecord } from "./shared.js";
 
 const loadResolveManifestContractOwnerPluginId = createLazyRuntimeNamedExport(
@@ -598,7 +599,9 @@ export async function resolveRuntimeWebProviderSelection<
       }
     } else {
       if (!selectedProvider && unresolvedWithoutFallback.length > 0) {
-        failUnresolvedNoFallback(unresolvedWithoutFallback[0]);
+        failUnresolvedNoFallback(
+          expectDefined(unresolvedWithoutFallback[0], "unresolved without fallback entry at 0"),
+        );
       }
 
       if (selectedProvider) {
diff --git a/src/security/audit-extra.sync.ts b/src/security/audit-extra.sync.ts
index 82dead75f5fc..24eaf7673ec5 100644
--- a/src/security/audit-extra.sync.ts
+++ b/src/security/audit-extra.sync.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Runs synchronous extra security audit checks.
 import {
   normalizeOptionalLowercaseString,
@@ -309,17 +310,21 @@ function editDistance(a: string, b: string): number {
   const dp: number[] = Array.from({ length: b.length + 1 }, (_, j) => j);
 
   for (let i = 1; i <= a.length; i++) {
-    let prev = dp[0];
+    let prev = expectDefined(dp[0], "dp entry at 0");
     dp[0] = i;
     for (let j = 1; j <= b.length; j++) {
       const temp = dp[j];
       const cost = a[i - 1] === b[j - 1] ? 0 : 1;
-      dp[j] = Math.min(dp[j] + 1, dp[j - 1] + 1, prev + cost);
-      prev = temp;
+      dp[j] = Math.min(
+        expectDefined(dp[j], "dp entry at j") + 1,
+        expectDefined(dp[j - 1], "dp entry at j 1") + 1,
+        prev + cost,
+      );
+      prev = expectDefined(temp, "audit extra.sync temp");
     }
   }
 
-  return dp[b.length];
+  return expectDefined(dp[b.length], "dp entry at b.length");
 }
 
 function suggestKnownNodeCommands(unknown: string, known: Set<string>): string[] {
diff --git a/src/security/dm-policy-shared.ts b/src/security/dm-policy-shared.ts
index 1730c9e28b31..87e0c592bdc2 100644
--- a/src/security/dm-policy-shared.ts
+++ b/src/security/dm-policy-shared.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Shares direct-message policy normalization for channel audits.
 import { normalizeStringEntries } from "@openclaw/normalization-core/string-normalization";
 import { resolveGroupAllowFromSources } from "../channels/allow-from.js";
@@ -32,7 +33,9 @@ export function resolvePinnedMainDmOwnerFromAllowlist(params: {
         .filter((entry): entry is string => Boolean(entry)),
     ),
   );
-  return normalizedOwners.length === 1 ? normalizedOwners[0] : null;
+  return normalizedOwners.length === 1
+    ? expectDefined(normalizedOwners[0], "normalized owners entry at 0")
+    : null;
 }
 
 /** @deprecated Use `resolveChannelMessageIngress` from `openclaw/plugin-sdk/channel-ingress-runtime`. */
diff --git a/src/security/external-content.ts b/src/security/external-content.ts
index a6e9cc8ab8d8..9bbd1cd0efe3 100644
--- a/src/security/external-content.ts
+++ b/src/security/external-content.ts
@@ -225,7 +225,7 @@ function foldMarkerTextWithIndexMap(input: string): FoldedMarkerMatch {
   const originalEndByFoldedIndex: number[] = [];
 
   for (let index = 0; index < input.length; index += 1) {
-    const char = input[index];
+    const char = input.charAt(index);
     if (isMarkerIgnorableChar(char)) {
       continue;
     }
diff --git a/src/security/safe-regex.ts b/src/security/safe-regex.ts
index ee1d57f04261..9dd5500f61f4 100644
--- a/src/security/safe-regex.ts
+++ b/src/security/safe-regex.ts
@@ -1,4 +1,5 @@
 // Performs lightweight safe-regex checks for user-supplied patterns.
+import { expectDefined } from "@openclaw/normalization-core";
 type QuantifierRead = {
   consumed: number;
   minRepeat: number;
@@ -102,7 +103,7 @@ function readQuantifier(source: string, index: number): QuantifierRead | null {
   }
 
   let i = index + 1;
-  while (i < source.length && /\d/.test(source[i])) {
+  while (i < source.length && /\d/.test(source.charAt(i))) {
     i += 1;
   }
   if (i === index + 1) {
@@ -114,7 +115,7 @@ function readQuantifier(source: string, index: number): QuantifierRead | null {
   if (source[i] === ",") {
     i += 1;
     const maxStart = i;
-    while (i < source.length && /\d/.test(source[i])) {
+    while (i < source.length && /\d/.test(source.charAt(i))) {
       i += 1;
     }
     maxRepeat = i === maxStart ? null : Number.parseInt(source.slice(maxStart, i), 10);
@@ -196,7 +197,7 @@ function analyzeTokensForNestedRepetition(tokens: PatternToken[]): boolean {
   const frames: ParseFrame[] = [createParseFrame()];
 
   const emitToken = (token: TokenState) => {
-    const frame = frames[frames.length - 1];
+    const frame = expectDefined(frames[frames.length - 1], "frames entry at frames.length 1");
     frame.lastToken = token;
     if (token.containsRepetition) {
       frame.containsRepetition = true;
@@ -252,7 +253,7 @@ function analyzeTokensForNestedRepetition(tokens: PatternToken[]): boolean {
     }
 
     if (token.kind === "alternation") {
-      const frame = frames[frames.length - 1];
+      const frame = expectDefined(frames[frames.length - 1], "frames entry at frames.length 1");
       frame.hasAlternation = true;
       recordAlternative(frame);
       frame.branchMinLength = 0;
@@ -261,7 +262,7 @@ function analyzeTokensForNestedRepetition(tokens: PatternToken[]): boolean {
       continue;
     }
 
-    const frame = frames[frames.length - 1];
+    const frame = expectDefined(frames[frames.length - 1], "frames entry at frames.length 1");
     const previousToken = frame.lastToken;
     if (!previousToken) {
       continue;
diff --git a/src/sessions/session-id-resolution.ts b/src/sessions/session-id-resolution.ts
index 88e8def7d4fe..c9cf64f8247e 100644
--- a/src/sessions/session-id-resolution.ts
+++ b/src/sessions/session-id-resolution.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Session id resolution helpers resolve user-provided session references.
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import type { SessionEntry } from "../config/sessions.js";
@@ -67,11 +68,11 @@ function collapseAliasMatches(matches: NormalizedSessionIdMatch[]): NormalizedSe
 
   return Array.from(grouped.values(), (group) => {
     if (group.length === 1) {
-      return group[0];
+      return expectDefined(group[0], "normalized session id match");
     }
     // Aliases that normalize to the same request key represent one session.
     // Prefer freshest canonical key so ambiguity only reports distinct sessions.
-    return [...group].toSorted((a, b) => {
+    const sorted = [...group].toSorted((a, b) => {
       const timeDiff = compareNormalizedUpdatedAtDescending(a, b);
       if (timeDiff !== 0) {
         return timeDiff;
@@ -80,7 +81,8 @@ function collapseAliasMatches(matches: NormalizedSessionIdMatch[]): NormalizedSe
         return a.isCanonicalSessionKey ? -1 : 1;
       }
       return compareStoreKeys(a.normalizedSessionKey, b.normalizedSessionKey);
-    })[0];
+    });
+    return expectDefined(sorted[0], "freshest normalized session id match");
   });
 }
 
@@ -112,7 +114,11 @@ export function resolveSessionIdMatchSelection(
     normalizeSessionIdMatches(matches, normalizeLowercaseStringOrEmpty(sessionId)),
   );
   if (canonicalMatches.length === 1) {
-    return { kind: "selected", sessionKey: canonicalMatches[0].sessionKey };
+    return {
+      kind: "selected",
+      sessionKey: expectDefined(canonicalMatches[0], "canonical matches capture group 0")
+        .sessionKey,
+    };
   }
 
   const structuralMatches = canonicalMatches.filter((match) => match.isStructural);
diff --git a/src/shared/assistant-error-format.ts b/src/shared/assistant-error-format.ts
index 6e6659f16451..53ee03a30d54 100644
--- a/src/shared/assistant-error-format.ts
+++ b/src/shared/assistant-error-format.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Assistant error formatting helpers normalize assistant-visible error payloads.
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 const ERROR_PAYLOAD_PREFIX_RE =
@@ -160,7 +161,7 @@ export function parseApiErrorInfo(raw?: string): ApiErrorInfo | null {
   const httpPrefixMatch = candidate.match(/^(\d{3})\s+(.+)$/s);
   if (httpPrefixMatch) {
     httpCode = httpPrefixMatch[1];
-    candidate = httpPrefixMatch[2].trim();
+    candidate = expectDefined(httpPrefixMatch[2], "http prefix match capture group 2").trim();
   }
 
   const payload = parseApiErrorPayload(candidate);
@@ -234,7 +235,7 @@ export function formatRawAssistantErrorForUi(raw?: string): string {
 
   const httpMatch = trimmed.match(HTTP_STATUS_PREFIX_RE);
   if (httpMatch) {
-    const rest = httpMatch[2].trim();
+    const rest = expectDefined(httpMatch[2], "http match capture group 2").trim();
     if (!rest.startsWith("{")) {
       return `HTTP ${httpMatch[1]}: ${rest}`;
     }
diff --git a/src/shared/human-list.ts b/src/shared/human-list.ts
index aeedf61a8f0a..dbd971c0649f 100644
--- a/src/shared/human-list.ts
+++ b/src/shared/human-list.ts
@@ -1,10 +1,10 @@
-/** Formats a short human-readable disjunction such as "A, B, or C". */
+import { expectDefined } from "@openclaw/normalization-core"; /** Formats a short human-readable disjunction such as "A, B, or C". */
 export function formatHumanList(values: readonly string[]): string {
   if (values.length === 0) {
     return "";
   }
   if (values.length === 1) {
-    return values[0];
+    return expectDefined(values[0], "values entry at 0");
   }
   if (values.length === 2) {
     return `${values[0]} or ${values[1]}`;
diff --git a/src/shared/levenshtein-distance.ts b/src/shared/levenshtein-distance.ts
index 7ca9f72b61e5..77ebf7f4df3a 100644
--- a/src/shared/levenshtein-distance.ts
+++ b/src/shared/levenshtein-distance.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 export function levenshteinDistance(left: string, right: string): number {
   if (left === right) {
     return 0;
@@ -19,14 +20,14 @@ export function levenshteinDistance(left: string, right: string): number {
     for (let rightIndex = 0; rightIndex < right.length; rightIndex += 1) {
       const cost = left[leftIndex] === right[rightIndex] ? 0 : 1;
       current[rightIndex + 1] = Math.min(
-        current[rightIndex] + 1,
-        previous[rightIndex + 1] + 1,
-        previous[rightIndex] + cost,
+        expectDefined(current[rightIndex], "current entry at right index") + 1,
+        expectDefined(previous[rightIndex + 1], "previous entry at right index + 1") + 1,
+        expectDefined(previous[rightIndex], "previous entry at right index") + cost,
       );
     }
     const nextPrevious = current;
     current = previous;
     previous = nextPrevious;
   }
-  return previous[right.length];
+  return expectDefined(previous[right.length], "previous entry at right.length");
 }
diff --git a/src/shared/text-chunking.ts b/src/shared/text-chunking.ts
index 0f7800e520a3..76142b2aa19e 100644
--- a/src/shared/text-chunking.ts
+++ b/src/shared/text-chunking.ts
@@ -48,7 +48,8 @@ export function chunkTextByBreakResolver(
     }
     // Keep separator ownership with the boundary: one matched separator is
     // consumed here, and any adjacent whitespace is trimmed before the next window.
-    const brokeOnSeparator = safeBreakIdx < remaining.length && /\s/.test(remaining[safeBreakIdx]);
+    const brokeOnSeparator =
+      safeBreakIdx < remaining.length && /\s/.test(remaining.charAt(safeBreakIdx));
     const nextStart = Math.min(remaining.length, safeBreakIdx + (brokeOnSeparator ? 1 : 0));
     remaining = remaining.slice(nextStart).trimStart();
   }
diff --git a/src/shared/text/assistant-visible-text.ts b/src/shared/text/assistant-visible-text.ts
index 55f1bc87e640..1ee52d29be94 100644
--- a/src/shared/text/assistant-visible-text.ts
+++ b/src/shared/text/assistant-visible-text.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Assistant visible text helpers strip hidden reasoning and control marker text.
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { stripPlainTextToolCallBlocks } from "../../../packages/tool-call-repair/src/index.js";
@@ -96,7 +97,7 @@ function parseXmlTagAt(text: string, start: number): ParsedToolCallTag | null {
   }
 
   let cursor = start + 1;
-  while (cursor < text.length && /\s/.test(text[cursor])) {
+  while (cursor < text.length && /\s/.test(text.charAt(cursor))) {
     cursor += 1;
   }
 
@@ -104,7 +105,7 @@ function parseXmlTagAt(text: string, start: number): ParsedToolCallTag | null {
   if (text[cursor] === "/") {
     isClose = true;
     cursor += 1;
-    while (cursor < text.length && /\s/.test(text[cursor])) {
+    while (cursor < text.length && /\s/.test(text.charAt(cursor))) {
       cursor += 1;
     }
   }
@@ -114,7 +115,7 @@ function parseXmlTagAt(text: string, start: number): ParsedToolCallTag | null {
     return null;
   }
   cursor += 1;
-  while (cursor < text.length && /[A-Za-z0-9_.:-]/.test(text[cursor])) {
+  while (cursor < text.length && /[A-Za-z0-9_.:-]/.test(text.charAt(cursor))) {
     cursor += 1;
   }
 
@@ -201,7 +202,7 @@ function startsWithNestedJsonToolCallPayload(text: string, start: number): boole
     return false;
   }
   let cursor = start;
-  while (cursor < text.length && /\s/.test(text[cursor])) {
+  while (cursor < text.length && /\s/.test(text.charAt(cursor))) {
     cursor += 1;
   }
   const nestedTag = parseToolCallTagAt(text, cursor);
@@ -235,7 +236,7 @@ function isLikelyStandaloneFunctionToolCall(
     idx -= 1;
   }
 
-  return idx < 0 || text[idx] === "\n" || text[idx] === "\r" || /[.!?:]/.test(text[idx]);
+  return idx < 0 || text[idx] === "\n" || text[idx] === "\r" || /[.!?:]/.test(text.charAt(idx));
 }
 
 function isStandaloneOpeningTagLine(
@@ -320,7 +321,7 @@ function findAdjacentOpeningToolCallTag(
   tagName: string,
 ): ParsedToolCallTag | null {
   let idx = start;
-  while (idx < text.length && /\s/.test(text[idx])) {
+  while (idx < text.length && /\s/.test(text.charAt(idx))) {
     idx += 1;
   }
   if (text[idx] !== "<") {
@@ -366,7 +367,7 @@ function isDanglingFunctionParameterParent(text: string, tag: ParsedToolCallTag)
     return false;
   }
   let cursor = tag.end;
-  while (cursor < text.length && /\s/.test(text[cursor])) {
+  while (cursor < text.length && /\s/.test(text.charAt(cursor))) {
     cursor += 1;
   }
   const nextTag = parseXmlTagAt(text, cursor);
@@ -425,7 +426,7 @@ function unwrapStandaloneParameterTags(text: string): string {
     if (tag.isClose) {
       const openIndex = openTags.findLastIndex((entry) => entry.name === tag.tagName);
       if (openIndex !== -1) {
-        const opening = openTags[openIndex];
+        const opening = expectDefined(openTags[openIndex], "open tags entry at open index");
         if (opening.unwrap) {
           const contentEnd =
             opening.trimBoundaryLineBreaks &&
diff --git a/src/shared/text/code-regions.ts b/src/shared/text/code-regions.ts
index ad99b2044ff8..5cec81dd03e5 100644
--- a/src/shared/text/code-regions.ts
+++ b/src/shared/text/code-regions.ts
@@ -1,4 +1,5 @@
 // Code region helpers find fenced and inline code spans in Markdown text.
+import { expectDefined } from "@openclaw/normalization-core";
 export interface CodeRegion {
   start: number;
   end: number;
@@ -10,8 +11,12 @@ export function findCodeRegions(text: string): CodeRegion[] {
 
   const fencedRe = /(^|\n)(```|~~~)[^\n]*\n[\s\S]*?(?:\n\2|$)/g;
   for (const match of text.matchAll(fencedRe)) {
-    const start = (match.index ?? 0) + match[1].length;
-    regions.push({ start, end: start + match[0].length - match[1].length });
+    const start =
+      (match.index ?? 0) + expectDefined(match[1], "code regions regex capture 1").length;
+    regions.push({
+      start,
+      end: start + match[0].length - expectDefined(match[1], "code regions regex capture 1").length,
+    });
   }
 
   const inlineRe = /`+[^`]+`+/g;
diff --git a/src/shared/text/reasoning-tags.ts b/src/shared/text/reasoning-tags.ts
index b8c59f672f5e..2634aad9ddd9 100644
--- a/src/shared/text/reasoning-tags.ts
+++ b/src/shared/text/reasoning-tags.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Reasoning tag helpers find and remove model reasoning tag blocks from text.
 import { findCodeRegions, isInsideCode } from "./code-regions.js";
 import { findFinalTagMatches } from "./final-tags.js";
@@ -89,7 +90,7 @@ export function stripReasoningTagsFromText(
     }
 
     for (let i = finalMatches.length - 1; i >= 0; i--) {
-      const m = finalMatches[i];
+      const m = expectDefined(finalMatches[i], "final matches capture group i");
       if (!m.inCode) {
         cleaned = cleaned.slice(0, m.start) + cleaned.slice(m.start + m.length);
       }
diff --git a/src/skills/security/scanner.ts b/src/skills/security/scanner.ts
index 79b9b4e8a346..7c31cdf436f5 100644
--- a/src/skills/security/scanner.ts
+++ b/src/skills/security/scanner.ts
@@ -1,6 +1,7 @@
 // Skill security scanner inspects skill files and manifests for unsafe patterns.
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { hasErrnoCode } from "../../infra/errors.js";
 import { isPathInside } from "../../security/scan-paths.js";
@@ -409,8 +410,7 @@ export function scanSource(source: string, filePath: string): SkillScanFinding[]
       continue;
     }
 
-    for (let i = 0; i < lines.length; i++) {
-      const line = lines[i];
+    for (const [i, line] of lines.entries()) {
       const match = rule.pattern.exec(line);
       if (!match) {
         continue;
@@ -422,7 +422,7 @@ export function scanSource(source: string, filePath: string): SkillScanFinding[]
 
       // Special handling for suspicious-network: check port
       if (rule.ruleId === "suspicious-network") {
-        const port = Number.parseInt(match[1], 10);
+        const port = Number.parseInt(expectDefined(match[1], "scanner regex capture 1"), 10);
         if (STANDARD_PORTS.has(port)) {
           continue;
         }
diff --git a/src/skills/workshop/service.ts b/src/skills/workshop/service.ts
index 05cef237e3f4..aec794b851aa 100644
--- a/src/skills/workshop/service.ts
+++ b/src/skills/workshop/service.ts
@@ -1,5 +1,6 @@
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import type { OpenClawConfig } from "../../config/types.openclaw.js";
 import { readLocalFileSafely, root, walkDirectory } from "../../infra/fs-safe.js";
@@ -231,7 +232,10 @@ export async function resolvePendingSkillProposal(input: {
       .join(", ");
     throw new Error(`Multiple pending skill proposals matched ${name}: ${candidates}`);
   }
-  const matched = await readRequiredProposal(matches[0].id, input.workspaceDir);
+  const matched = await readRequiredProposal(
+    expectDefined(matches[0], "matches capture group 0").id,
+    input.workspaceDir,
+  );
   if (matched.record.status !== "pending") {
     throw new Error(
       `Only pending proposals can be revised. Current status: ${matched.record.status}.`,
diff --git a/src/status/agent-runtime-label.ts b/src/status/agent-runtime-label.ts
index 2355da56e3c8..7096cdc19f5c 100644
--- a/src/status/agent-runtime-label.ts
+++ b/src/status/agent-runtime-label.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Agent runtime label helpers format provider, model, and runtime labels.
 import {
   normalizeOptionalLowercaseString,
@@ -55,5 +56,5 @@ export function resolveAgentRuntimeLabel(args: {
     );
   }
 
-  return AGENT_RUNTIME_LABELS.openclaw;
+  return expectDefined(AGENT_RUNTIME_LABELS.openclaw, "OpenClaw runtime label");
 }
diff --git a/src/talk/audio-codec.ts b/src/talk/audio-codec.ts
index 8470530288a3..5560f5a6b751 100644
--- a/src/talk/audio-codec.ts
+++ b/src/talk/audio-codec.ts
@@ -1,4 +1,4 @@
-/**
+import { expectDefined } from "@openclaw/normalization-core"; /**
  * PCM resampling and G.711 mu-law conversion helpers for Talk audio bridges.
  *
  * Telephony providers generally expect 8 kHz mu-law frames, while local audio
@@ -189,8 +189,10 @@ export function resamplePcm(
         ? sampleBandlimitedWithCoefficients(
             inputView,
             Math.floor((i * inputSampleRate) / outputSampleRate),
-            kernel.coefficients[(i * kernel.inputStep) % kernel.phaseCount] ??
-              kernel.coefficients[0],
+            expectDefined(
+              kernel.coefficients[(i * kernel.inputStep) % kernel.phaseCount],
+              "coefficients entry at (i * kernel.input step) % kernel.phase count",
+            ) ?? kernel.coefficients[0],
           )
         : sampleBandlimited(inputView, i * ratio, cutoffCyclesPerSample),
     );
diff --git a/src/test-utils/chunk-test-helpers.ts b/src/test-utils/chunk-test-helpers.ts
index 43cc1f2a5f88..d394641ec528 100644
--- a/src/test-utils/chunk-test-helpers.ts
+++ b/src/test-utils/chunk-test-helpers.ts
@@ -1,4 +1,4 @@
-/** Markdown chunk helpers shared by prompt and streaming tests. */
+import { expectDefined } from "@openclaw/normalization-core"; /** Markdown chunk helpers shared by prompt and streaming tests. */
 export function countLines(text: string): number {
   return text.split("\n").length;
 }
@@ -10,9 +10,9 @@ export function hasBalancedFences(chunk: string): boolean {
     if (!match) {
       continue;
     }
-    const marker = match[2];
+    const marker = expectDefined(match[2], "chunk test helpers regex capture 2");
     if (!open) {
-      open = { markerChar: marker[0], markerLen: marker.length };
+      open = { markerChar: marker.charAt(0), markerLen: marker.length };
       continue;
     }
     if (open.markerChar === marker[0] && marker.length >= open.markerLen) {
diff --git a/src/test-utils/temp-home.ts b/src/test-utils/temp-home.ts
index 407c94fea5fd..0c225670ed8f 100644
--- a/src/test-utils/temp-home.ts
+++ b/src/test-utils/temp-home.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { captureEnv, setTestEnvValue } from "./env.js";
 import { cleanupSessionStateForTest } from "./session-state-cleanup.js";
 
@@ -59,7 +60,7 @@ export async function createTempHomeEnv(prefix: string): Promise<TempHomeEnv> {
   if (process.platform === "win32") {
     const match = home.match(/^([A-Za-z]:)(.*)$/);
     if (match) {
-      setTestEnvValue("HOMEDRIVE", match[1]);
+      setTestEnvValue("HOMEDRIVE", expectDefined(match[1], "temp home regex capture 1"));
       setTestEnvValue("HOMEPATH", match[2] || "\\");
     }
   }
diff --git a/src/test-utils/tracked-temp-dirs.ts b/src/test-utils/tracked-temp-dirs.ts
index 98284430569f..e30dff15b0c3 100644
--- a/src/test-utils/tracked-temp-dirs.ts
+++ b/src/test-utils/tracked-temp-dirs.ts
@@ -2,6 +2,7 @@
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 
 /** Allocates temp directories under reusable roots with explicit cleanup control. */
 export function createTrackedTempDirs() {
@@ -58,7 +59,7 @@ export function createTrackedTempDirs() {
       );
       await Promise.all(
         roots.flatMap((dir, i) =>
-          dirlists[i].map((entry) =>
+          expectDefined(dirlists[i], "dirlists entry at i").map((entry) =>
             fs.rm(path.join(dir, entry), { recursive: true, force: true }),
           ),
         ),
diff --git a/src/tui/osc8-hyperlinks.ts b/src/tui/osc8-hyperlinks.ts
index 9f67f2b717d3..5e47b1d56ee8 100644
--- a/src/tui/osc8-hyperlinks.ts
+++ b/src/tui/osc8-hyperlinks.ts
@@ -1,4 +1,5 @@
 // Regex patterns for ANSI escape sequences (constructed from strings to
+import { expectDefined } from "@openclaw/normalization-core";
 // satisfy the no-control-regex lint rule).
 const SGR_PATTERN = "\\x1b\\[[0-9;]*m";
 const OSC8_PATTERN = "\\x1b\\]8;;.*?(?:\\x07|\\x1b\\\\)";
@@ -32,7 +33,10 @@ function trimUnbalancedTrailingParens(url: string): string {
 }
 
 function hasUrlContent(url: string): boolean {
-  const authority = url.slice(url.indexOf("://") + 3).split(/[/?#]/, 1)[0];
+  const authority = expectDefined(
+    url.slice(url.indexOf("://") + 3).split(/[/?#]/, 1)[0],
+    'url.slice(url.index of("://") + 3).split(/[/?#]/, 1) entry at 0',
+  );
   return /[\p{L}\p{N}]/u.test(authority) || /^\[[0-9a-f:.]+\](?::\d+)?$/i.test(authority);
 }
 
@@ -50,8 +54,8 @@ export function extractUrls(markdown: string): string[] {
   );
   let m: RegExpExecArray | null;
   while ((m = mdLinkRe.exec(markdown)) !== null) {
-    if (hasUrlContent(m[1])) {
-      urls.add(m[1]);
+    if (hasUrlContent(expectDefined(m[1], "m capture group 1"))) {
+      urls.add(expectDefined(m[1], "m capture group 1"));
     }
   }
 
@@ -284,7 +288,12 @@ export function addOsc8Hyperlinks(lines: string[], urls: string[]): string[] {
   const visibleLines = lines.map(stripAnsi);
 
   return lines.map((line, index) => {
-    const result = findUrlRanges(visibleLines[index], urls, pending, visibleLines[index + 1]);
+    const result = findUrlRanges(
+      expectDefined(visibleLines[index], "visible lines entry at index"),
+      urls,
+      pending,
+      visibleLines[index + 1],
+    );
     pending = result.pending;
     return applyOsc8Ranges(line, result.ranges);
   });
diff --git a/src/tui/theme/theme.ts b/src/tui/theme/theme.ts
index 37679d665d27..6396cc654daf 100644
--- a/src/tui/theme/theme.ts
+++ b/src/tui/theme/theme.ts
@@ -5,6 +5,7 @@ import type {
   SelectListTheme,
   SettingsListTheme,
 } from "@earendil-works/pi-tui";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalLowercaseString } from "@openclaw/normalization-core/string-coerce";
 import chalk from "chalk";
 import type { SearchableSelectListTheme } from "../components/searchable-select-list.js";
@@ -66,9 +67,18 @@ function isLightBackground(): boolean {
         return bg >= 244;
       }
       const cubeIndex = bg - 16;
-      const bVal = XTERM_LEVELS[cubeIndex % 6];
-      const gVal = XTERM_LEVELS[Math.floor(cubeIndex / 6) % 6];
-      const rVal = XTERM_LEVELS[Math.floor(cubeIndex / 36)];
+      const bVal = expectDefined(
+        XTERM_LEVELS[cubeIndex % 6],
+        "xterm levels entry at cube index % 6",
+      );
+      const gVal = expectDefined(
+        XTERM_LEVELS[Math.floor(cubeIndex / 6) % 6],
+        "xterm levels entry at math.floor(cube index / 6) % 6",
+      );
+      const rVal = expectDefined(
+        XTERM_LEVELS[Math.floor(cubeIndex / 36)],
+        "xterm levels entry at math.floor(cube index / 36)",
+      );
       return pickHigherContrastText(rVal, gVal, bVal);
     }
   }
diff --git a/src/tui/tui-waiting.ts b/src/tui/tui-waiting.ts
index ba895c589f73..d397ba34b81f 100644
--- a/src/tui/tui-waiting.ts
+++ b/src/tui/tui-waiting.ts
@@ -36,7 +36,7 @@ function shimmerText(theme: MinimalTheme, text: string, tick: number) {
 
   let out = "";
   for (let i = 0; i < text.length; i++) {
-    const ch = text[i];
+    const ch = text.charAt(i);
     out += i >= start && i <= end ? hi(ch) : theme.dim(ch);
   }
   return out;
diff --git a/src/utils/directive-tags.ts b/src/utils/directive-tags.ts
index 1ee225652af1..95524953a922 100644
--- a/src/utils/directive-tags.ts
+++ b/src/utils/directive-tags.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 // Directive tag helpers parse inline directive tags from user text.
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 
@@ -63,7 +64,9 @@ function normalizeDirectiveWhitespace(text: string): string {
     .replace(/\n{3,}/g, "\n\n")
     .trimEnd();
 
-  return normalized.replace(blockPlaceholderRe, (_, i) => blocks[Number(i)]);
+  return normalized.replace(blockPlaceholderRe, (_, i) =>
+    expectDefined(blocks[Number(i)], "blocks entry at number(i)"),
+  );
 }
 
 type StripInlineDirectiveTagsResult = {
diff --git a/src/utils/message-channel.ts b/src/utils/message-channel.ts
index c925af60f374..718fd04aa24c 100644
--- a/src/utils/message-channel.ts
+++ b/src/utils/message-channel.ts
@@ -8,7 +8,7 @@ import {
   normalizeGatewayClientName,
 } from "../../packages/gateway-protocol/src/client-info.js";
 import { listBundledChannelCatalogEntries } from "../channels/bundled-channel-catalog-read.js";
-import { getChatChannelMeta } from "../channels/chat-meta.js";
+import { findChatChannelMeta } from "../channels/chat-meta.js";
 import { getRegisteredChannelPluginMeta, normalizeChatChannelId } from "../channels/registry.js";
 export {
   isDeliverableMessageChannel,
@@ -103,7 +103,7 @@ export function isMarkdownCapableMessageChannel(raw?: string | null): boolean {
   }
   const builtInChannel = normalizeChatChannelId(channel);
   if (builtInChannel) {
-    const builtInMeta = getChatChannelMeta(builtInChannel);
+    const builtInMeta = findChatChannelMeta(builtInChannel);
     if (builtInMeta) {
       return builtInMeta.markdownCapable === true;
     }
diff --git a/src/utils/queue-helpers.ts b/src/utils/queue-helpers.ts
index ec07cd9632d8..88fa3b7cac3f 100644
--- a/src/utils/queue-helpers.ts
+++ b/src/utils/queue-helpers.ts
@@ -1,3 +1,4 @@
+import { expectDefined } from "@openclaw/normalization-core";
 /**
  * Shared queue overflow, debounce, and collection helpers.
  *
@@ -135,23 +136,23 @@ export function applyQueueDropPolicy<T>(params: {
   // Only mutate the queue when enough victims exist so a partial drop cannot
   // admit overflow when the queue is full of in-flight/protected work.
   const victimIndices: number[] = [];
-  for (
-    let index = 0;
-    index < params.queue.items.length && victimIndices.length < dropCount;
-    index += 1
-  ) {
-    const item = params.queue.items[index];
+  for (const [index, item] of params.queue.items.entries()) {
     if (params.inFlight?.has(item) || params.isProtected?.(item) === true) {
       continue;
     }
     victimIndices.push(index);
+    if (victimIndices.length === dropCount) {
+      break;
+    }
   }
   if (victimIndices.length < dropCount) {
     return false;
   }
   const dropped: T[] = [];
   for (let i = victimIndices.length - 1; i >= 0; i -= 1) {
-    dropped.unshift(...params.queue.items.splice(victimIndices[i], 1));
+    dropped.unshift(
+      ...params.queue.items.splice(expectDefined(victimIndices[i], "victim indices entry at i"), 1),
+    );
   }
   params.onDrop?.(dropped);
   if (params.queue.dropPolicy === "summarize") {
diff --git a/src/utils/run-with-concurrency.ts b/src/utils/run-with-concurrency.ts
index 805d2cb9fe16..dad82129d1a3 100644
--- a/src/utils/run-with-concurrency.ts
+++ b/src/utils/run-with-concurrency.ts
@@ -1,4 +1,4 @@
-/** Controls whether the worker pool keeps scheduling after a task failure. */
+import { expectDefined } from "@openclaw/normalization-core"; /** Controls whether the worker pool keeps scheduling after a task failure. */
 export type ConcurrencyErrorMode = "continue" | "stop";
 
 /** Options for running a fixed list of promise factories through a bounded worker pool. */
@@ -52,7 +52,7 @@ export async function runTasksWithConcurrency<T>(
         return;
       }
       try {
-        results[index] = await tasks[index]();
+        results[index] = await expectDefined(tasks[index], "tasks entry at index")();
       } catch (error) {
         if (!hasError) {
           firstError = error;
diff --git a/src/utils/shell-argv.ts b/src/utils/shell-argv.ts
index 2eb6f4207aa1..a90bfcd5a808 100644
--- a/src/utils/shell-argv.ts
+++ b/src/utils/shell-argv.ts
@@ -14,7 +14,7 @@ export function hasTopLevelShellControlOperator(raw: string): boolean {
   let wordStart = true;
 
   for (let i = 0; i < raw.length; i += 1) {
-    const ch = raw[i];
+    const ch = raw.charAt(i);
     if (escaped) {
       escaped = false;
       wordStart = false;
@@ -69,7 +69,7 @@ export function splitShellArgs(raw: string): string[] | null {
   };
 
   for (let i = 0; i < raw.length; i += 1) {
-    const ch = raw[i];
+    const ch = raw.charAt(i);
     if (escaped) {
       buf += ch;
       escaped = false;
diff --git a/src/utils/usage-format.ts b/src/utils/usage-format.ts
index b338c11f1570..d94eb41b56c7 100644
--- a/src/utils/usage-format.ts
+++ b/src/utils/usage-format.ts
@@ -3,6 +3,7 @@
  * Keep this module synchronous; request paths call it while rendering usage summaries.
  */
 import path from "node:path";
+import { expectDefined } from "@openclaw/normalization-core";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
 import { resolveDefaultAgentDir } from "../agents/agent-scope-config.js";
 import { modelKey, normalizeModelRef, normalizeProviderId } from "../agents/model-selection.js";
@@ -661,7 +662,7 @@ function selectPricingTier(tiers: PricingTier[], input: number): PricingTier | u
   }
 
   for (let index = sortedTiers.length - 1; index >= 0; index -= 1) {
-    const tier = sortedTiers[index];
+    const tier = expectDefined(sortedTiers[index], "sorted tiers entry at index");
     if (input >= tier.range[0]) {
       return tier;
     }
diff --git a/src/wizard/clack-navigation-prompts.ts b/src/wizard/clack-navigation-prompts.ts
index 453c064222b7..51903ae9f79c 100644
--- a/src/wizard/clack-navigation-prompts.ts
+++ b/src/wizard/clack-navigation-prompts.ts
@@ -31,6 +31,7 @@ import {
   type SelectOptions,
   type TextOptions,
 } from "@clack/prompts";
+import { expectDefined } from "@openclaw/normalization-core";
 import type { WizardPromptNavigation } from "./prompts.js";
 
 type PromptOption<Value> = {
@@ -164,7 +165,10 @@ export function selectWithNavigationFooter<Value>(
           const submitPrefix = showGuide ? `${styleText("gray", S_BAR)}  ` : "";
           const wrappedLines = wrapTextWithPrefix(
             opts.output,
-            selectOptionRenderer(this.options[this.cursor], "selected"),
+            selectOptionRenderer(
+              expectDefined(this.options[this.cursor], "options entry at this.cursor"),
+              "selected",
+            ),
             submitPrefix,
           );
           return `${title}${wrappedLines}`;
@@ -173,7 +177,10 @@ export function selectWithNavigationFooter<Value>(
           const cancelPrefix = showGuide ? `${styleText("gray", S_BAR)}  ` : "";
           const wrappedLines = wrapTextWithPrefix(
             opts.output,
-            selectOptionRenderer(this.options[this.cursor], "cancelled"),
+            selectOptionRenderer(
+              expectDefined(this.options[this.cursor], "options entry at this.cursor"),
+              "cancelled",
+            ),
             cancelPrefix,
           );
           return `${title}${wrappedLines}${showGuide ? `\n${styleText("gray", S_BAR)}` : ""}`;