diff --git a/src/agents/cli-runner/prepare.ts b/src/agents/cli-runner/prepare.ts
index 4901fbf34e5..8389aee398f 100644
--- a/src/agents/cli-runner/prepare.ts
+++ b/src/agents/cli-runner/prepare.ts
@@ -107,7 +107,11 @@ export async function prepareCliRunContext(
     authCredential = authStore.profiles[effectiveAuthProfileId];
   }
   const extraSystemPrompt = params.extraSystemPrompt?.trim() ?? "";
-  const extraSystemPromptHash = hashCliSessionText(extraSystemPrompt);
+  // Use the static portion (excluding per-message inbound metadata) for session reuse hashing.
+  // Per-message metadata (timestamps, message IDs) changes every turn and must not trigger session resets.
+  const extraSystemPromptHash = hashCliSessionText(params.extraSystemPromptStatic?.trim() || undefined) ?? hashCliSessionText(extraSystemPrompt);
+
+
   const modelId = (params.model ?? "default").trim() || "default";
   const normalizedModel = normalizeCliModel(modelId, backendResolved.config);
   const modelDisplay = `${params.provider}/${modelId}`;
diff --git a/src/agents/cli-runner/types.ts b/src/agents/cli-runner/types.ts
index ecae4de5e3e..aa3bfa13322 100644
--- a/src/agents/cli-runner/types.ts
+++ b/src/agents/cli-runner/types.ts
@@ -23,6 +23,8 @@ export type RunCliAgentParams = {
   timeoutMs: number;
   runId: string;
   extraSystemPrompt?: string;
+  /** Static portion of extraSystemPrompt (excluding per-message inbound metadata) for session reuse hashing. */
+  extraSystemPromptStatic?: string;
   streamParams?: import("../command/types.js").AgentStreamParams;
   ownerNumbers?: string[];
   cliSessionId?: string;
diff --git a/src/auto-reply/reply/get-reply-run.ts b/src/auto-reply/reply/get-reply-run.ts
index f2cc3554f5b..24cc9887a4f 100644
--- a/src/auto-reply/reply/get-reply-run.ts
+++ b/src/auto-reply/reply/get-reply-run.ts
@@ -305,6 +305,18 @@ export async function runPreparedReply(
       fullAccessBlockedReason: fullAccessState.blockedReason,
     }),
   ].filter(Boolean);
+  // Static parts only (no per-message inbound metadata) for CLI session reuse hashing.
+  const extraSystemPromptStaticParts = [
+    groupChatContext,
+    groupIntro,
+    groupSystemPrompt,
+    buildExecOverridePromptHint({
+      execOverrides,
+      elevatedLevel: resolvedElevatedLevel,
+      fullAccessAvailable: fullAccessState.available,
+      fullAccessBlockedReason: fullAccessState.blockedReason,
+    }),
+  ].filter(Boolean);
   const baseBody = sessionCtx.BodyStripped ?? sessionCtx.Body ?? "";
   // Use CommandBody/RawBody for bare reset detection (clean message without structural context).
   const rawBodyTrimmed = (ctx.CommandBody ?? ctx.RawBody ?? ctx.Body ?? "").trim();
@@ -734,6 +746,7 @@ export async function runPreparedReply(
       ownerNumbers: command.ownerList.length > 0 ? command.ownerList : undefined,
       inputProvenance: ctx.InputProvenance ?? sessionCtx.InputProvenance,
       extraSystemPrompt: extraSystemPromptParts.join("\n\n") || undefined,
+      extraSystemPromptStatic: extraSystemPromptStaticParts.join("\n\n") || undefined,
       skipProviderRuntimeHints: useFastReplyRuntime,
       ...(!useFastReplyRuntime &&
       isReasoningTagProvider(provider, {