diff --git a/docs/.generated/plugin-sdk-api-baseline.sha256 b/docs/.generated/plugin-sdk-api-baseline.sha256
index ee9d46892d0..13f4915848e 100644
--- a/docs/.generated/plugin-sdk-api-baseline.sha256
+++ b/docs/.generated/plugin-sdk-api-baseline.sha256
@@ -1,2 +1,2 @@
-dd840593b93b3ee264cef645f7ba65a04c5049fe71d7d0877c29e95e4a6405f7  plugin-sdk-api-baseline.json
-bec5bda680942c05400a3d74685202d631682fb6c1b8512da660e5679f65b0e7  plugin-sdk-api-baseline.jsonl
+a25794a905166b6cc5879855f0220d93a3686b3d7d46ef6eb931cff9f42a9c36  plugin-sdk-api-baseline.json
+aeaee8496792b31443bdd37ab6b8499c590663500463d3a6a2033c6b804d9c73  plugin-sdk-api-baseline.jsonl
diff --git a/scripts/plugin-sdk-surface-report.mjs b/scripts/plugin-sdk-surface-report.mjs
index 6b614fa55bb..7e1adce3421 100644
--- a/scripts/plugin-sdk-surface-report.mjs
+++ b/scripts/plugin-sdk-surface-report.mjs
@@ -27,7 +27,7 @@ const budgets = {
     process.env.OPENCLAW_PLUGIN_SDK_MAX_PUBLIC_FUNCTION_EXPORTS ?? 4656,
   ),
   publicDeprecatedExports: Number(
-    process.env.OPENCLAW_PLUGIN_SDK_MAX_PUBLIC_DEPRECATED_EXPORTS ?? 3700,
+    process.env.OPENCLAW_PLUGIN_SDK_MAX_PUBLIC_DEPRECATED_EXPORTS ?? 3800,
   ),
   publicWildcardReexports: Number(
     process.env.OPENCLAW_PLUGIN_SDK_MAX_PUBLIC_WILDCARD_REEXPORTS ?? 207,
diff --git a/src/agents/anthropic-payload-policy.ts b/src/agents/anthropic-payload-policy.ts
index 4d046bf19f1..665a3343237 100644
--- a/src/agents/anthropic-payload-policy.ts
+++ b/src/agents/anthropic-payload-policy.ts
@@ -4,8 +4,10 @@ import {
   stripSystemPromptCacheBoundary,
 } from "./system-prompt-cache-boundary.js";
 
+/** @deprecated Anthropic-family provider payload helper; do not use from third-party plugins. */
 export type AnthropicServiceTier = "auto" | "standard_only";
 
+/** @deprecated Anthropic-family provider payload helper; do not use from third-party plugins. */
 export type AnthropicEphemeralCacheControl = {
   type: "ephemeral";
   ttl?: "1h";
@@ -20,6 +22,7 @@ type AnthropicPayloadPolicyInput = {
   serviceTier?: AnthropicServiceTier;
 };
 
+/** @deprecated Anthropic-family provider payload helper; do not use from third-party plugins. */
 export type AnthropicPayloadPolicy = {
   allowsServiceTier: boolean;
   cacheControl: AnthropicEphemeralCacheControl | undefined;
@@ -176,6 +179,7 @@ function applyAnthropicCacheControlToMessages(
   }
 }
 
+/** @deprecated Anthropic-family provider payload helper; do not use from third-party plugins. */
 export function resolveAnthropicPayloadPolicy(
   input: AnthropicPayloadPolicyInput,
 ): AnthropicPayloadPolicy {
@@ -197,6 +201,7 @@ export function resolveAnthropicPayloadPolicy(
   };
 }
 
+/** @deprecated Anthropic-family provider payload helper; do not use from third-party plugins. */
 export function applyAnthropicPayloadPolicyToParams(
   payloadObj: Record<string, unknown>,
   policy: AnthropicPayloadPolicy,
@@ -223,6 +228,7 @@ export function applyAnthropicPayloadPolicyToParams(
   applyAnthropicCacheControlToMessages(payloadObj.messages, policy.cacheControl);
 }
 
+/** @deprecated Anthropic-family provider payload helper; do not use from third-party plugins. */
 export function applyAnthropicEphemeralCacheControlMarkers(
   payloadObj: Record<string, unknown>,
 ): void {
diff --git a/src/agents/auth-profiles/constants.ts b/src/agents/auth-profiles/constants.ts
index 9e0ba5207f8..bf32e0397a4 100644
--- a/src/agents/auth-profiles/constants.ts
+++ b/src/agents/auth-profiles/constants.ts
@@ -7,9 +7,12 @@ export {
 
 export const AUTH_STORE_VERSION = 1;
 
+/** @deprecated Anthropic provider-owned CLI profile id; do not use from third-party plugins. */
 export const CLAUDE_CLI_PROFILE_ID = "anthropic:claude-cli";
+/** @deprecated OpenAI Codex provider-owned CLI profile id; do not use from third-party plugins. */
 export const CODEX_CLI_PROFILE_ID = "openai-codex:codex-cli";
 export const OPENAI_CODEX_DEFAULT_PROFILE_ID = "openai-codex:default";
+/** @deprecated MiniMax provider-owned CLI profile id; do not use from third-party plugins. */
 export const MINIMAX_CLI_PROFILE_ID = "minimax-portal:minimax-cli";
 
 export const AUTH_STORE_LOCK_OPTIONS = {
diff --git a/src/agents/cli-credentials.ts b/src/agents/cli-credentials.ts
index 3d8adbb4719..5e0c9343e9c 100644
--- a/src/agents/cli-credentials.ts
+++ b/src/agents/cli-credentials.ts
@@ -450,6 +450,7 @@ export function readClaudeCliCredentials(options?: {
   return parseClaudeCliOauthCredential(data.claudeAiOauth);
 }
 
+/** @deprecated Anthropic provider-owned CLI credential helper; do not use from third-party plugins. */
 export function readClaudeCliCredentialsCached(options?: {
   allowKeychainPrompt?: boolean;
   ttlMs?: number;
diff --git a/src/agents/gpt5-prompt-overlay.ts b/src/agents/gpt5-prompt-overlay.ts
index 5c081d1bf47..7d0c33a0ed3 100644
--- a/src/agents/gpt5-prompt-overlay.ts
+++ b/src/agents/gpt5-prompt-overlay.ts
@@ -12,6 +12,7 @@ const OPENAI_FAMILY_GPT5_PROMPT_OVERLAY_PROVIDERS = new Set([
   "openai-codex",
 ]);
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export const GPT5_FRIENDLY_CHAT_PROMPT_OVERLAY = `## Interaction Style
 
 Be warm, collaborative, and quietly supportive.
@@ -36,6 +37,7 @@ Avoid walls of text, long preambles, and repetitive restatement.
 Occasional emoji are welcome when they fit naturally, especially for warmth or brief celebration; keep them sparse.
 Keep replies concise by default; friendly does not mean verbose.`;
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export const GPT5_HEARTBEAT_PROMPT_OVERLAY = `### Heartbeats
 
 The purpose of heartbeats is to make you feel magical and proactive. Come to life and start proactively doing things that are important.
@@ -55,8 +57,10 @@ If the current state is materially unchanged and you do not have something genui
 If there is a clear standing goal or workstream and no stronger interruption, the wake should usually advance it in some concrete way. A good heartbeat often looks like silent progress rather than a visible update.
 Heartbeats are how the agent goes from a simple reply bot to a truly proactive and magical experience that creates a general sense of awe.`;
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export const GPT5_FRIENDLY_PROMPT_OVERLAY = `${GPT5_FRIENDLY_CHAT_PROMPT_OVERLAY}\n\n${GPT5_HEARTBEAT_PROMPT_OVERLAY}`;
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export const GPT5_BEHAVIOR_CONTRACT = `<persona_latch>
 Keep the established persona and tone across turns unless higher-priority instructions override it.
 Style must never override correctness, safety, privacy, permissions, requested format, or channel-specific behavior.
@@ -94,8 +98,10 @@ For code or artifacts, prefer the smallest meaningful gate: test, typecheck, lin
 If no gate can run, state why.
 </completion_contract>`;
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export type Gpt5PromptOverlayMode = "friendly" | "off";
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export function normalizeGpt5PromptOverlayMode(value: unknown): Gpt5PromptOverlayMode | undefined {
   const normalized = normalizeOptionalLowercaseString(value);
   if (normalized === "off") {
@@ -107,6 +113,7 @@ export function normalizeGpt5PromptOverlayMode(value: unknown): Gpt5PromptOverla
   return undefined;
 }
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export function resolveGpt5PromptOverlayMode(
   config?: OpenClawConfig,
   legacyPluginConfig?: Record<string, unknown>,
@@ -125,11 +132,13 @@ export function resolveGpt5PromptOverlayMode(
   );
 }
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export function isGpt5ModelId(modelId?: string): boolean {
   const normalized = normalizeOptionalLowercaseString(modelId);
   return normalized ? GPT5_MODEL_ID_PATTERN.test(normalized) : false;
 }
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export function resolveGpt5SystemPromptContribution(params: {
   config?: OpenClawConfig;
   providerId?: string;
@@ -156,6 +165,7 @@ export function resolveGpt5SystemPromptContribution(params: {
   };
 }
 
+/** @deprecated OpenAI/Codex provider-owned prompt overlay helper; do not use from third-party plugins. */
 export function renderGpt5PromptOverlay(params: {
   config?: OpenClawConfig;
   providerId?: string;
diff --git a/src/agents/model-auth-markers.ts b/src/agents/model-auth-markers.ts
index 547b6d6160b..c592caad065 100644
--- a/src/agents/model-auth-markers.ts
+++ b/src/agents/model-auth-markers.ts
@@ -2,9 +2,11 @@ import type { SecretRefSource } from "../config/types.secrets.js";
 import { listOpenClawPluginManifestMetadata } from "../plugins/manifest-metadata-scan.js";
 import { listKnownProviderEnvApiKeyNames } from "./model-auth-env-vars.js";
 
+/** @deprecated MiniMax provider-owned marker; do not use from third-party plugins. */
 export const MINIMAX_OAUTH_MARKER = "minimax-oauth";
 export const OAUTH_API_KEY_MARKER_PREFIX = "oauth:";
 export const OLLAMA_LOCAL_AUTH_MARKER = "ollama-local";
+/** @deprecated Bundled local-provider marker; do not use from third-party plugins. */
 export const CUSTOM_LOCAL_AUTH_MARKER = "custom-local";
 export const GCP_VERTEX_CREDENTIALS_MARKER = "gcp-vertex-credentials";
 export const NON_ENV_SECRETREF_MARKER = "secretref-managed"; // pragma: allowlist secret
diff --git a/src/agents/openai-text-verbosity.ts b/src/agents/openai-text-verbosity.ts
index cd5ba92274c..11cc76f4350 100644
--- a/src/agents/openai-text-verbosity.ts
+++ b/src/agents/openai-text-verbosity.ts
@@ -1,6 +1,7 @@
 import { normalizeOptionalLowercaseString } from "../shared/string-coerce.js";
 import { log } from "./pi-embedded-runner/logger.js";
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export type OpenAITextVerbosity = "low" | "medium" | "high";
 
 function normalizeOpenAITextVerbosity(value: unknown): OpenAITextVerbosity | undefined {
@@ -14,6 +15,7 @@ function normalizeOpenAITextVerbosity(value: unknown): OpenAITextVerbosity | und
   return undefined;
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function resolveOpenAITextVerbosity(
   extraParams: Record<string, unknown> | undefined,
 ): OpenAITextVerbosity | undefined {
diff --git a/src/agents/pi-embedded-runner/anthropic-family-tool-payload-compat.ts b/src/agents/pi-embedded-runner/anthropic-family-tool-payload-compat.ts
index 398dc96c910..96990cc76df 100644
--- a/src/agents/pi-embedded-runner/anthropic-family-tool-payload-compat.ts
+++ b/src/agents/pi-embedded-runner/anthropic-family-tool-payload-compat.ts
@@ -124,6 +124,7 @@ function normalizeOpenAiStringModeAnthropicToolChoice(toolChoice: unknown): unkn
   return toolChoice;
 }
 
+/** @deprecated Anthropic-family provider stream helper; do not use from third-party plugins. */
 export function createAnthropicToolPayloadCompatibilityWrapper(
   baseStreamFn: StreamFn | undefined,
   options?: AnthropicToolPayloadCompatibilityOptions,
@@ -160,6 +161,7 @@ export function createAnthropicToolPayloadCompatibilityWrapper(
   };
 }
 
+/** @deprecated Anthropic-family provider stream helper; do not use from third-party plugins. */
 export function createOpenAIAnthropicToolPayloadCompatibilityWrapper(
   baseStreamFn: StreamFn | undefined,
 ): StreamFn {
diff --git a/src/agents/pi-embedded-runner/minimax-stream-wrappers.ts b/src/agents/pi-embedded-runner/minimax-stream-wrappers.ts
index 6890be2235c..b8a6e37071d 100644
--- a/src/agents/pi-embedded-runner/minimax-stream-wrappers.ts
+++ b/src/agents/pi-embedded-runner/minimax-stream-wrappers.ts
@@ -19,6 +19,7 @@ function isMinimaxAnthropicMessagesModel(model: { api?: unknown; provider?: unkn
   );
 }
 
+/** @deprecated MiniMax provider-owned stream helper; do not use from third-party plugins. */
 export function createMinimaxFastModeWrapper(
   baseStreamFn: StreamFn | undefined,
   fastMode: boolean,
@@ -50,6 +51,7 @@ export function createMinimaxFastModeWrapper(
  * content. Disable thinking in the outgoing payload so MiniMax does not produce
  * reasoning_content deltas during streaming.
  */
+/** @deprecated MiniMax provider-owned stream helper; do not use from third-party plugins. */
 export function createMinimaxThinkingDisabledWrapper(baseStreamFn: StreamFn | undefined): StreamFn {
   const underlying = baseStreamFn ?? streamSimple;
   return (model, context, options) => {
diff --git a/src/agents/pi-embedded-runner/moonshot-thinking-stream-wrappers.ts b/src/agents/pi-embedded-runner/moonshot-thinking-stream-wrappers.ts
index 77a3a09df7d..5e108ce6bf8 100644
--- a/src/agents/pi-embedded-runner/moonshot-thinking-stream-wrappers.ts
+++ b/src/agents/pi-embedded-runner/moonshot-thinking-stream-wrappers.ts
@@ -67,6 +67,7 @@ function isPinnedToolChoice(toolChoice: unknown): boolean {
   return typeValue === "tool" || typeValue === "function";
 }
 
+/** @deprecated Moonshot provider-owned stream helper; do not use from third-party plugins. */
 export function resolveMoonshotThinkingType(params: {
   configuredThinking: unknown;
   thinkingLevel?: ThinkLevel;
@@ -81,12 +82,14 @@ export function resolveMoonshotThinkingType(params: {
   return params.thinkingLevel === "off" ? "disabled" : "enabled";
 }
 
+/** @deprecated Moonshot provider-owned stream helper; do not use from third-party plugins. */
 export function resolveMoonshotThinkingKeep(params: {
   configuredThinking: unknown;
 }): MoonshotThinkingKeep | undefined {
   return normalizeMoonshotThinkingKeep(params.configuredThinking);
 }
 
+/** @deprecated Moonshot provider-owned stream helper; do not use from third-party plugins. */
 export function createMoonshotThinkingWrapper(
   baseStreamFn: StreamFn | undefined,
   thinkingType?: MoonshotThinkingType,
diff --git a/src/agents/pi-embedded-runner/openai-stream-wrappers.ts b/src/agents/pi-embedded-runner/openai-stream-wrappers.ts
index ece348ed847..ce6ab89c772 100644
--- a/src/agents/pi-embedded-runner/openai-stream-wrappers.ts
+++ b/src/agents/pi-embedded-runner/openai-stream-wrappers.ts
@@ -198,6 +198,7 @@ function normalizeOpenAIServiceTier(value: unknown): OpenAIServiceTier | undefin
   return undefined;
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function resolveOpenAIServiceTier(
   extraParams: Record<string, unknown> | undefined,
 ): OpenAIServiceTier | undefined {
@@ -239,6 +240,7 @@ function normalizeOpenAIFastMode(value: unknown): boolean | undefined {
   return undefined;
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function resolveOpenAIFastMode(
   extraParams: Record<string, unknown> | undefined,
 ): boolean | undefined {
@@ -260,6 +262,7 @@ function applyOpenAIFastModePayloadOverrides(params: {
   }
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIResponsesContextManagementWrapper(
   baseStreamFn: StreamFn | undefined,
   extraParams: Record<string, unknown> | undefined,
@@ -295,6 +298,7 @@ export function createOpenAIResponsesContextManagementWrapper(
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIReasoningCompatibilityWrapper(
   baseStreamFn: StreamFn | undefined,
 ): StreamFn {
@@ -312,6 +316,7 @@ export function createOpenAIReasoningCompatibilityWrapper(
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIStringContentWrapper(baseStreamFn: StreamFn | undefined): StreamFn {
   const underlying = baseStreamFn ?? streamSimple;
   return (model, context, options) => {
@@ -327,6 +332,7 @@ export function createOpenAIStringContentWrapper(baseStreamFn: StreamFn | undefi
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAICompletionsStrictMessageKeysWrapper(
   baseStreamFn: StreamFn | undefined,
 ): StreamFn {
@@ -344,6 +350,7 @@ export function createOpenAICompletionsStrictMessageKeysWrapper(
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAICompletionsToolsCompatWrapper(
   baseStreamFn: StreamFn | undefined,
 ): StreamFn {
@@ -360,6 +367,7 @@ export function createOpenAICompletionsToolsCompatWrapper(
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIThinkingLevelWrapper(
   baseStreamFn: StreamFn | undefined,
   thinkingLevel?: ThinkLevel,
@@ -407,6 +415,7 @@ export function createOpenAIThinkingLevelWrapper(
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIFastModeWrapper(baseStreamFn: StreamFn | undefined): StreamFn {
   const underlying = baseStreamFn ?? streamSimple;
   return (model, context, options) => {
@@ -434,6 +443,7 @@ export function createOpenAIFastModeWrapper(baseStreamFn: StreamFn | undefined):
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIServiceTierWrapper(
   baseStreamFn: StreamFn | undefined,
   serviceTier: OpenAIServiceTier,
@@ -451,6 +461,7 @@ export function createOpenAIServiceTierWrapper(
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAITextVerbosityWrapper(
   baseStreamFn: StreamFn | undefined,
   verbosity: OpenAITextVerbosity,
@@ -482,6 +493,7 @@ export function createOpenAITextVerbosityWrapper(
     });
   };
 }
+/** @deprecated OpenAI Codex provider-owned stream helper; do not use from third-party plugins. */
 export function createCodexNativeWebSearchWrapper(
   baseStreamFn: StreamFn | undefined,
   params: { config?: OpenClawConfig; agentDir?: string },
@@ -534,6 +546,7 @@ export function createCodexNativeWebSearchWrapper(
     });
   };
 }
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIDefaultTransportWrapper(baseStreamFn: StreamFn | undefined): StreamFn {
   const underlying = baseStreamFn ?? streamSimple;
   return (model, context, options) => {
@@ -545,6 +558,7 @@ export function createOpenAIDefaultTransportWrapper(baseStreamFn: StreamFn | und
   };
 }
 
+/** @deprecated OpenAI provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenAIAttributionHeadersWrapper(
   baseStreamFn: StreamFn | undefined,
   opts?: { codexNativeTransportStreamFn?: StreamFn },
diff --git a/src/agents/pi-embedded-runner/openrouter-model-capabilities.ts b/src/agents/pi-embedded-runner/openrouter-model-capabilities.ts
index 74c66323474..4ef13c844ad 100644
--- a/src/agents/pi-embedded-runner/openrouter-model-capabilities.ts
+++ b/src/agents/pi-embedded-runner/openrouter-model-capabilities.ts
@@ -270,6 +270,8 @@ function ensureOpenRouterModelCache(): void {
  * Known cached entries return immediately. Unknown entries wait for at most
  * one catalog fetch, then leave sync resolution to read from the populated
  * cache on the same request.
+ *
+ * @deprecated OpenRouter provider-owned catalog helper; do not use from third-party plugins.
  */
 export async function loadOpenRouterModelCapabilities(modelId: string): Promise<void> {
   ensureOpenRouterModelCache();
@@ -292,6 +294,8 @@ export async function loadOpenRouterModelCapabilities(modelId: string): Promise<
  *
  * If a model is not found but the cache exists, a background refresh is
  * triggered in case it's a newly added model not yet in the cache.
+ *
+ * @deprecated OpenRouter provider-owned catalog helper; do not use from third-party plugins.
  */
 export function getOpenRouterModelCapabilities(
   modelId: string,
diff --git a/src/agents/pi-embedded-runner/proxy-stream-wrappers.ts b/src/agents/pi-embedded-runner/proxy-stream-wrappers.ts
index b7c5616faf7..5a658728561 100644
--- a/src/agents/pi-embedded-runner/proxy-stream-wrappers.ts
+++ b/src/agents/pi-embedded-runner/proxy-stream-wrappers.ts
@@ -150,6 +150,7 @@ function normalizeProxyReasoningPayload(payload: unknown, thinkingLevel?: ThinkL
   }
 }
 
+/** @deprecated OpenRouter provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenRouterSystemCacheWrapper(baseStreamFn: StreamFn | undefined): StreamFn {
   const underlying = baseStreamFn ?? streamSimple;
   return (model, context, options) => {
@@ -181,6 +182,7 @@ export function createOpenRouterSystemCacheWrapper(baseStreamFn: StreamFn | unde
   };
 }
 
+/** @deprecated OpenRouter provider-owned stream helper; do not use from third-party plugins. */
 export function createOpenRouterWrapper(
   baseStreamFn: StreamFn | undefined,
   thinkingLevel?: ThinkLevel,
@@ -214,12 +216,14 @@ export function createOpenRouterWrapper(
   };
 }
 
+/** @deprecated Proxy provider-owned stream helper; do not use from third-party plugins. */
 export function isProxyReasoningUnsupported(modelId: string): boolean {
   const trimmed = normalizeOptionalLowercaseString(modelId);
   const slashIndex = trimmed?.indexOf("/") ?? -1;
   return slashIndex > 0 && trimmed?.slice(0, slashIndex) === "x-ai";
 }
 
+/** @deprecated Kilocode provider-owned stream helper; do not use from third-party plugins. */
 export function createKilocodeWrapper(
   baseStreamFn: StreamFn | undefined,
   thinkingLevel?: ThinkLevel,
diff --git a/src/agents/pi-embedded-runner/zai-stream-wrappers.ts b/src/agents/pi-embedded-runner/zai-stream-wrappers.ts
index e9778c31a82..6fb2ece7f34 100644
--- a/src/agents/pi-embedded-runner/zai-stream-wrappers.ts
+++ b/src/agents/pi-embedded-runner/zai-stream-wrappers.ts
@@ -5,6 +5,8 @@ import { streamWithPayloadPatch } from "./stream-payload-utils.js";
 /**
  * Inject `tool_stream=true` so tool-call deltas stream in real time.
  * Providers can disable this by setting `params.tool_stream=false`.
+ *
+ * @deprecated Provider-owned stream helper; do not use from third-party plugins.
  */
 export function createToolStreamWrapper(
   baseStreamFn: StreamFn | undefined,
@@ -22,4 +24,5 @@ export function createToolStreamWrapper(
   };
 }
 
+/** @deprecated Z.ai provider-owned stream helper; do not use from third-party plugins. */
 export const createZaiToolStreamWrapper = createToolStreamWrapper;
diff --git a/src/plugin-sdk/oauth-utils.ts b/src/plugin-sdk/oauth-utils.ts
index 6642cd5f502..8e9093d1a48 100644
--- a/src/plugin-sdk/oauth-utils.ts
+++ b/src/plugin-sdk/oauth-utils.ts
@@ -1,13 +1,21 @@
 import { createHash, randomBytes } from "node:crypto";
 
-/** Encode a flat object as application/x-www-form-urlencoded form data. */
+/**
+ * Encode a flat object as application/x-www-form-urlencoded form data.
+ *
+ * @deprecated OAuth provider-owned helper; keep this local to provider plugins instead.
+ */
 export function toFormUrlEncoded(data: Record<string, string>): string {
   return Object.entries(data)
     .map(([key, value]) => `${encodeURIComponent(key)}=${encodeURIComponent(value)}`)
     .join("&");
 }
 
-/** Generate a PKCE verifier/challenge pair suitable for OAuth authorization flows. */
+/**
+ * Generate a PKCE verifier/challenge pair suitable for OAuth authorization flows.
+ *
+ * @deprecated OAuth provider-owned helper; keep this local to provider plugins instead.
+ */
 export function generatePkceVerifierChallenge(): { verifier: string; challenge: string } {
   const verifier = randomBytes(32).toString("base64url");
   const challenge = createHash("sha256").update(verifier).digest("base64url");
diff --git a/src/plugin-sdk/provider-auth.ts b/src/plugin-sdk/provider-auth.ts
index ef42a5a86c4..7e4a17faa48 100644
--- a/src/plugin-sdk/provider-auth.ts
+++ b/src/plugin-sdk/provider-auth.ts
@@ -94,13 +94,20 @@ export {
 
 const COPILOT_TOKEN_URL = "https://api.github.com/copilot_internal/v2/token";
 
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export const COPILOT_EDITOR_VERSION = "vscode/1.96.2";
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export const COPILOT_USER_AGENT = "GitHubCopilotChat/0.26.7";
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export const COPILOT_EDITOR_PLUGIN_VERSION = "copilot-chat/0.35.0";
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export const COPILOT_GITHUB_API_VERSION = "2025-04-01";
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export const COPILOT_INTEGRATION_ID = "vscode-chat";
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export const DEFAULT_COPILOT_API_BASE_URL = "https://api.individual.githubcopilot.com";
 
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export type CachedCopilotToken = {
   token: string;
   expiresAt: number;
@@ -108,6 +115,7 @@ export type CachedCopilotToken = {
   integrationId?: string;
 };
 
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export function buildCopilotIdeHeaders(
   params: {
     includeApiVersion?: boolean;
@@ -177,6 +185,7 @@ function resolveCopilotProxyHost(proxyEp: string): string | null {
   }
 }
 
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export function deriveCopilotApiBaseUrlFromToken(token: string): string | null {
   const trimmed = token.trim();
   if (!trimmed) {
@@ -199,6 +208,7 @@ export function deriveCopilotApiBaseUrlFromToken(token: string): string | null {
   return resolveProviderEndpoint(baseUrl).endpointClass === "invalid" ? null : baseUrl;
 }
 
+/** @deprecated GitHub Copilot provider-owned helper; do not use from third-party plugins. */
 export async function resolveCopilotApiToken(params: {
   githubToken: string;
   env?: NodeJS.ProcessEnv;
diff --git a/src/plugin-sdk/provider-model-shared.ts b/src/plugin-sdk/provider-model-shared.ts
index abf12a36232..308c7a085c4 100644
--- a/src/plugin-sdk/provider-model-shared.ts
+++ b/src/plugin-sdk/provider-model-shared.ts
@@ -118,6 +118,7 @@ function getModelProviderHint(modelId: string): string | null {
   return trimmed.slice(0, slashIndex) || null;
 }
 
+/** @deprecated Proxy provider-owned model helper; do not use from third-party plugins. */
 export function isProxyReasoningUnsupportedModelHint(modelId: string): boolean {
   return getModelProviderHint(modelId) === "x-ai";
 }
@@ -131,10 +132,12 @@ function isClaudeOpus47ModelId(modelId: string): boolean {
   return matchesClaudeModelPrefix(modelId, CLAUDE_OPUS_47_MODEL_PREFIXES);
 }
 
+/** @deprecated Anthropic provider-owned model helper; do not use from third-party plugins. */
 export function isClaudeAdaptiveThinkingDefaultModelId(modelId: string): boolean {
   return matchesClaudeModelPrefix(modelId, CLAUDE_ADAPTIVE_THINKING_DEFAULT_MODEL_PREFIXES);
 }
 
+/** @deprecated Anthropic provider-owned model helper; do not use from third-party plugins. */
 export function resolveClaudeThinkingProfile(modelId: string): ProviderThinkingProfile {
   if (isClaudeOpus47ModelId(modelId)) {
     return {
@@ -232,18 +235,22 @@ export function buildProviderReplayFamilyHooks(
   throw new Error("Unsupported provider replay family");
 }
 
+/** @deprecated Provider-owned replay hook shortcut; use local provider hooks instead. */
 export const OPENAI_COMPATIBLE_REPLAY_HOOKS = buildProviderReplayFamilyHooks({
   family: "openai-compatible",
 });
 
+/** @deprecated Anthropic provider-owned replay hook shortcut; use local provider hooks instead. */
 export const ANTHROPIC_BY_MODEL_REPLAY_HOOKS = buildProviderReplayFamilyHooks({
   family: "anthropic-by-model",
 });
 
+/** @deprecated Anthropic provider-owned replay hook shortcut; use local provider hooks instead. */
 export const NATIVE_ANTHROPIC_REPLAY_HOOKS = buildProviderReplayFamilyHooks({
   family: "native-anthropic-by-model",
 });
 
+/** @deprecated Google provider-owned replay hook shortcut; use local provider hooks instead. */
 export const PASSTHROUGH_GEMINI_REPLAY_HOOKS = buildProviderReplayFamilyHooks({
   family: "passthrough-gemini",
 });
diff --git a/src/plugin-sdk/provider-stream-shared.ts b/src/plugin-sdk/provider-stream-shared.ts
index 3222bc6efc2..0b9faac5220 100644
--- a/src/plugin-sdk/provider-stream-shared.ts
+++ b/src/plugin-sdk/provider-stream-shared.ts
@@ -20,6 +20,7 @@ export function composeProviderStreamWrappers(
   );
 }
 
+/** @deprecated Bundled provider stream helper; do not use from third-party plugins. */
 export function defaultToolStreamExtraParams(
   extraParams?: Record<string, unknown>,
 ): Record<string, unknown> {
@@ -107,6 +108,7 @@ function stripTrailingAssistantPrefillMessages(payload: Record<string, unknown>)
   return stripped;
 }
 
+/** @deprecated Anthropic-family provider stream helper; do not use from third-party plugins. */
 export function stripTrailingAnthropicAssistantPrefillWhenThinking(
   payload: Record<string, unknown>,
 ): number {
@@ -116,6 +118,7 @@ export function stripTrailingAnthropicAssistantPrefillWhenThinking(
   return stripTrailingAssistantPrefillMessages(payload);
 }
 
+/** @deprecated Anthropic-family provider stream helper; do not use from third-party plugins. */
 export function createAnthropicThinkingPrefillPayloadWrapper(
   baseStreamFn: StreamFn | undefined,
   onStripped?: (stripped: number) => void,
@@ -133,8 +136,10 @@ export function createAnthropicThinkingPrefillPayloadWrapper(
   );
 }
 
+/** @deprecated OpenAI-compatible provider stream helper; do not use from third-party plugins. */
 export type OpenAICompatibleThinkingLevel = ProviderWrapStreamFnContext["thinkingLevel"];
 
+/** @deprecated OpenAI-compatible provider stream helper; do not use from third-party plugins. */
 export function isOpenAICompatibleThinkingEnabled(params: {
   thinkingLevel: OpenAICompatibleThinkingLevel;
   options: Parameters<StreamFn>[2];
@@ -148,7 +153,9 @@ export function isOpenAICompatibleThinkingEnabled(params: {
   return normalized !== "off" && normalized !== "none";
 }
 
+/** @deprecated DeepSeek provider stream helper; do not use from third-party plugins. */
 export type DeepSeekV4ThinkingLevel = ProviderWrapStreamFnContext["thinkingLevel"];
+/** @deprecated DeepSeek provider stream helper; do not use from third-party plugins. */
 export type DeepSeekV4ReasoningEffort = "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 
 function isDisabledDeepSeekV4ThinkingLevel(thinkingLevel: DeepSeekV4ThinkingLevel): boolean {
@@ -192,6 +199,7 @@ function ensureDeepSeekV4AssistantReasoningContent(payload: Record<string, unkno
   }
 }
 
+/** @deprecated DeepSeek provider stream helper; do not use from third-party plugins. */
 export function createDeepSeekV4OpenAICompatibleThinkingWrapper(params: {
   baseStreamFn: StreamFn | undefined;
   thinkingLevel: DeepSeekV4ThinkingLevel;
@@ -224,7 +232,9 @@ export function createDeepSeekV4OpenAICompatibleThinkingWrapper(params: {
   };
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export type GoogleThinkingLevel = "MINIMAL" | "LOW" | "MEDIUM" | "HIGH";
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export type GoogleThinkingInputLevel =
   | "off"
   | "minimal"
@@ -237,28 +247,34 @@ export type GoogleThinkingInputLevel =
 
 // Gemini 2.5 Pro only works in thinking mode and rejects thinkingBudget=0 with
 // "Budget 0 is invalid. This model only works in thinking mode."
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function isGoogleThinkingRequiredModel(modelId: string): boolean {
   return normalizeLowercaseStringOrEmpty(modelId).includes("gemini-2.5-pro");
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function isGoogleGemini25ThinkingBudgetModel(modelId: string): boolean {
   return /(?:^|\/)gemini-2\.5-/.test(normalizeLowercaseStringOrEmpty(modelId));
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function isGoogleGemini3ProModel(modelId: string): boolean {
   const normalized = normalizeLowercaseStringOrEmpty(modelId);
   return /(?:^|\/)gemini-(?:3(?:\.\d+)?-pro|pro-latest)(?:-|$)/.test(normalized);
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function isGoogleGemini3FlashModel(modelId: string): boolean {
   const normalized = normalizeLowercaseStringOrEmpty(modelId);
   return /(?:^|\/)gemini-(?:3(?:\.\d+)?-flash|flash(?:-lite)?-latest)(?:-|$)/.test(normalized);
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function isGoogleGemini3ThinkingLevelModel(modelId: string): boolean {
   return isGoogleGemini3ProModel(modelId) || isGoogleGemini3FlashModel(modelId);
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function resolveGoogleGemini3ThinkingLevel(params: {
   modelId?: string;
   thinkingLevel?: GoogleThinkingInputLevel;
@@ -329,6 +345,7 @@ export function resolveGoogleGemini3ThinkingLevel(params: {
   return "HIGH";
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function stripInvalidGoogleThinkingBudget(params: {
   thinkingConfig: Record<string, unknown>;
   modelId?: string;
@@ -384,6 +401,7 @@ function normalizeGemma4ThinkingLevel(value: unknown): "MINIMAL" | "HIGH" | unde
   }
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function sanitizeGoogleThinkingPayload(params: {
   payload: unknown;
   modelId?: string;
@@ -510,6 +528,7 @@ function sanitizeGoogleThinkingConfigContainer(params: {
   }
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function createGoogleThinkingPayloadWrapper(
   baseStreamFn: StreamFn | undefined,
   thinkingLevel?: GoogleThinkingInputLevel,
@@ -525,6 +544,7 @@ export function createGoogleThinkingPayloadWrapper(
   });
 }
 
+/** @deprecated Google provider-owned stream helper; do not use from third-party plugins. */
 export function createGoogleThinkingStreamWrapper(
   ctx: ProviderWrapStreamFnContext,
 ): NonNullable<ProviderWrapStreamFnContext["streamFn"]> {
diff --git a/src/plugin-sdk/provider-stream.ts b/src/plugin-sdk/provider-stream.ts
index 08183596598..e8c6a7e47f2 100644
--- a/src/plugin-sdk/provider-stream.ts
+++ b/src/plugin-sdk/provider-stream.ts
@@ -143,15 +143,22 @@ export function buildProviderStreamFamilyHooks(
   throw new Error("Unsupported provider stream family");
 }
 
+/** @deprecated Google provider-owned stream hook shortcut; use local provider hooks instead. */
 export const GOOGLE_THINKING_STREAM_HOOKS = buildProviderStreamFamilyHooks("google-thinking");
+/** @deprecated Kilocode provider-owned stream hook shortcut; use local provider hooks instead. */
 export const KILOCODE_THINKING_STREAM_HOOKS = buildProviderStreamFamilyHooks("kilocode-thinking");
+/** @deprecated Moonshot provider-owned stream hook shortcut; use local provider hooks instead. */
 export const MOONSHOT_THINKING_STREAM_HOOKS = buildProviderStreamFamilyHooks("moonshot-thinking");
+/** @deprecated MiniMax provider-owned stream hook shortcut; use local provider hooks instead. */
 export const MINIMAX_FAST_MODE_STREAM_HOOKS = buildProviderStreamFamilyHooks("minimax-fast-mode");
+/** @deprecated OpenAI provider-owned stream hook shortcut; use local provider hooks instead. */
 export const OPENAI_RESPONSES_STREAM_HOOKS = buildProviderStreamFamilyHooks(
   "openai-responses-defaults",
 );
+/** @deprecated OpenRouter provider-owned stream hook shortcut; use local provider hooks instead. */
 export const OPENROUTER_THINKING_STREAM_HOOKS =
   buildProviderStreamFamilyHooks("openrouter-thinking");
+/** @deprecated Provider-owned stream hook shortcut; use local provider hooks instead. */
 export const TOOL_STREAM_DEFAULT_ON_HOOKS =
   buildProviderStreamFamilyHooks("tool-stream-default-on");
 
diff --git a/src/plugins/provider-auth-token.ts b/src/plugins/provider-auth-token.ts
index 1b8426a26d1..409e1d53ca6 100644
--- a/src/plugins/provider-auth-token.ts
+++ b/src/plugins/provider-auth-token.ts
@@ -17,12 +17,14 @@ function normalizeTokenProfileName(raw: string): string {
   return slug || DEFAULT_TOKEN_PROFILE_NAME;
 }
 
+/** @deprecated Provider-owned setup helper; do not use from third-party plugins. */
 export function buildTokenProfileId(params: { provider: string; name: string }): string {
   const provider = normalizeProviderId(params.provider);
   const name = normalizeTokenProfileName(params.name);
   return `${provider}:${name}`;
 }
 
+/** @deprecated Anthropic provider-owned setup helper; do not use from third-party plugins. */
 export function validateAnthropicSetupToken(raw: string): string | undefined {
   const trimmed = raw.trim();
   if (!trimmed) {
diff --git a/src/plugins/provider-model-compat.ts b/src/plugins/provider-model-compat.ts
index e088669c8d9..7f4e5a52c40 100644
--- a/src/plugins/provider-model-compat.ts
+++ b/src/plugins/provider-model-compat.ts
@@ -15,6 +15,7 @@ export function extractModelCompat(
   return modelOrCompat as ModelCompatConfig;
 }
 
+/** @deprecated Provider-owned model compat helper; do not use from third-party plugins. */
 export function applyModelCompatPatch<T extends { compat?: ModelCompatConfig }>(
   model: T,
   patch: ModelCompatConfig,
diff --git a/src/plugins/provider-replay-helpers.ts b/src/plugins/provider-replay-helpers.ts
index 8df8cbd2b77..c4edd59988c 100644
--- a/src/plugins/provider-replay-helpers.ts
+++ b/src/plugins/provider-replay-helpers.ts
@@ -10,6 +10,7 @@ import type {
   ProviderSanitizeReplayHistoryContext,
 } from "./types.js";
 
+/** @deprecated Provider replay helper; prefer provider-local replay hooks. */
 export function buildOpenAICompatibleReplayPolicy(
   modelApi: string | null | undefined,
   options: {
@@ -52,6 +53,7 @@ export function buildOpenAICompatibleReplayPolicy(
   };
 }
 
+/** @deprecated Anthropic-family provider replay helper; prefer provider-local replay hooks. */
 export function buildStrictAnthropicReplayPolicy(
   options: {
     dropThinkingBlocks?: boolean;
@@ -85,6 +87,8 @@ export function buildStrictAnthropicReplayPolicy(
  * thinking blocks from prior turns breaks prompt cache prefix matching.
  *
  * See: https://platform.claude.com/docs/en/build-with-claude/extended-thinking#differences-in-thinking-across-model-versions
+ *
+ * @deprecated Anthropic-family provider replay helper; prefer provider-local replay hooks.
  */
 export function shouldPreserveThinkingBlocks(modelId?: string): boolean {
   const id = normalizeLowercaseStringOrEmpty(modelId);
@@ -111,6 +115,7 @@ export function shouldPreserveThinkingBlocks(modelId?: string): boolean {
   return false;
 }
 
+/** @deprecated Anthropic-family provider replay helper; prefer provider-local replay hooks. */
 export function buildAnthropicReplayPolicyForModel(modelId?: string): ProviderReplayPolicy {
   const isClaude = normalizeLowercaseStringOrEmpty(modelId).includes("claude");
   return buildStrictAnthropicReplayPolicy({
@@ -118,6 +123,7 @@ export function buildAnthropicReplayPolicyForModel(modelId?: string): ProviderRe
   });
 }
 
+/** @deprecated Anthropic-family provider replay helper; prefer provider-local replay hooks. */
 export function buildNativeAnthropicReplayPolicyForModel(modelId?: string): ProviderReplayPolicy {
   const isClaude = normalizeLowercaseStringOrEmpty(modelId).includes("claude");
   return buildStrictAnthropicReplayPolicy({
@@ -127,6 +133,7 @@ export function buildNativeAnthropicReplayPolicyForModel(modelId?: string): Prov
   });
 }
 
+/** @deprecated Provider replay helper; prefer provider-local replay hooks. */
 export function buildHybridAnthropicOrOpenAIReplayPolicy(
   ctx: ProviderReplayPolicyContext,
   options: { anthropicModelDropThinkingBlocks?: boolean } = {},
@@ -158,6 +165,7 @@ function markGoogleTurnOrderingMarker(sessionState: ProviderReplaySessionState):
   });
 }
 
+/** @deprecated Google provider replay helper; prefer provider-local replay hooks. */
 export function buildGoogleGeminiReplayPolicy(): ProviderReplayPolicy {
   return {
     sanitizeMode: "full",
@@ -175,6 +183,7 @@ export function buildGoogleGeminiReplayPolicy(): ProviderReplayPolicy {
   };
 }
 
+/** @deprecated Google provider replay helper; prefer provider-local replay hooks. */
 export function buildPassthroughGeminiSanitizingReplayPolicy(
   modelId?: string,
 ): ProviderReplayPolicy {
@@ -194,6 +203,7 @@ export function buildPassthroughGeminiSanitizingReplayPolicy(
   };
 }
 
+/** @deprecated Google provider replay helper; prefer provider-local replay hooks. */
 export function sanitizeGoogleGeminiReplayHistory(
   ctx: ProviderSanitizeReplayHistoryContext,
 ): AgentMessage[] {
@@ -208,6 +218,7 @@ export function sanitizeGoogleGeminiReplayHistory(
   return messages;
 }
 
+/** @deprecated Provider replay helper; prefer provider-local replay hooks. */
 export function resolveTaggedReasoningOutputMode(): ProviderReasoningOutputMode {
   return "tagged";
 }