diff --git a/apps/server/src/provider/Layers/ClaudeAdapter.test.ts b/apps/server/src/provider/Layers/ClaudeAdapter.test.ts
index e127701c7..78e64f382 100644
--- a/apps/server/src/provider/Layers/ClaudeAdapter.test.ts
+++ b/apps/server/src/provider/Layers/ClaudeAdapter.test.ts
@@ -2473,6 +2473,57 @@ describe("ClaudeAdapterLive", () => {
     );
   });
 
+  it.effect(
+    "restores default permission mode on sendTurn when interactionMode is chat for approval-required sessions",
+    () => {
+      const harness = makeHarness();
+      return Effect.gen(function* () {
+        const adapter = yield* ClaudeAdapter;
+
+        const session = yield* adapter.startSession({
+          threadId: THREAD_ID,
+          provider: "claudeAgent",
+          runtimeMode: "approval-required",
+        });
+
+        yield* adapter.sendTurn({
+          threadId: session.threadId,
+          input: "plan this",
+          interactionMode: "plan",
+          attachments: [],
+        });
+
+        const turnCompletedFiber = yield* Stream.filter(
+          adapter.streamEvents,
+          (event) => event.type === "turn.completed",
+        ).pipe(Stream.runHead, Effect.forkChild);
+
+        harness.query.emit({
+          type: "result",
+          subtype: "success",
+          is_error: false,
+          errors: [],
+          session_id: "sdk-session-approval-plan-restore",
+          uuid: "result-approval-plan",
+        } as unknown as SDKMessage);
+
+        yield* Fiber.join(turnCompletedFiber);
+
+        yield* adapter.sendTurn({
+          threadId: session.threadId,
+          input: "now answer directly",
+          interactionMode: "chat",
+          attachments: [],
+        });
+
+        assert.deepEqual(harness.query.setPermissionModeCalls, ["plan", "default"]);
+      }).pipe(
+        Effect.provideService(Random.Random, makeDeterministicRandomService()),
+        Effect.provide(harness.layer),
+      );
+    },
+  );
+
   it.effect("does not call setPermissionMode when interactionMode is absent", () => {
     const harness = makeHarness();
     return Effect.gen(function* () {
diff --git a/apps/server/src/provider/Layers/ClaudeAdapter.ts b/apps/server/src/provider/Layers/ClaudeAdapter.ts
index 1f45b8569..4b6e4e1c0 100644
--- a/apps/server/src/provider/Layers/ClaudeAdapter.ts
+++ b/apps/server/src/provider/Layers/ClaudeAdapter.ts
@@ -157,7 +157,7 @@ interface ClaudeSessionContext {
   readonly query: ClaudeQueryRuntime;
   streamFiber: Fiber.Fiber<void, Error> | undefined;
   readonly startedAt: string;
-  readonly basePermissionMode: PermissionMode | undefined;
+  readonly basePermissionMode: PermissionMode;
   resumeSessionId: string | undefined;
   readonly pendingApprovals: Map<ApprovalRequestId, PendingApproval>;
   readonly pendingUserInputs: Map<ApprovalRequestId, PendingUserInput>;
@@ -2790,6 +2790,7 @@ function makeClaudeAdapter(options?: ClaudeAdapterLiveOptions) {
         const permissionMode =
           toPermissionMode(providerOptions?.permissionMode) ??
           (input.runtimeMode === "full-access" ? "bypassPermissions" : undefined);
+        const basePermissionMode = permissionMode ?? "default";
         const settings = {
           ...(typeof thinking === "boolean" ? { alwaysThinkingEnabled: thinking } : {}),
           ...(fastMode ? { fastMode: true } : {}),
@@ -2859,7 +2860,7 @@ function makeClaudeAdapter(options?: ClaudeAdapterLiveOptions) {
           query: queryRuntime,
           streamFiber: undefined,
           startedAt,
-          basePermissionMode: permissionMode,
+          basePermissionMode,
           resumeSessionId: sessionId,
           pendingApprovals,
           pendingUserInputs,
@@ -2965,8 +2966,7 @@ function makeClaudeAdapter(options?: ClaudeAdapterLiveOptions) {
           });
         } else if (input.interactionMode === "chat" || input.interactionMode === "code") {
           yield* Effect.tryPromise({
-            try: () =>
-              context.query.setPermissionMode(context.basePermissionMode ?? "bypassPermissions"),
+            try: () => context.query.setPermissionMode(context.basePermissionMode),
             catch: (cause) => toRequestError(input.threadId, "turn/setPermissionMode", cause),
           });
         }