diff --git a/packages/server/src/server/agent/providers/claude-agent.integration.test.ts b/packages/server/src/server/agent/providers/claude-agent.integration.test.ts
index 10f10f01c..e109d47e4 100644
--- a/packages/server/src/server/agent/providers/claude-agent.integration.test.ts
+++ b/packages/server/src/server/agent/providers/claude-agent.integration.test.ts
@@ -213,6 +213,25 @@ describe("ClaudeAgentSession integration", () => {
     }
   }, 60_000);
 
+  test.runIf(canRunClaudeIntegration)(
+    "keeps bypassPermissions available after a thinking-option restart",
+    async () => {
+      const handle = await createSession({
+        cwdPrefix: "claude-agent-bypass-restart-",
+        modeId: "bypassPermissions",
+      });
+
+      try {
+        await handle.session.setMode("acceptEdits");
+        await handle.session.setThinkingOption("high");
+        await expect(handle.session.setMode("bypassPermissions")).resolves.toBeUndefined();
+      } finally {
+        await cleanupSession(handle);
+      }
+    },
+    60_000,
+  );
+
   test.runIf(canRunClaudeIntegration)(
     "supportedModels returns the current abstract Claude SDK model shape",
     async () => {
diff --git a/packages/server/src/server/agent/providers/claude-agent.redesign.test.ts b/packages/server/src/server/agent/providers/claude-agent.redesign.test.ts
index 37fd2a201..74bd40656 100644
--- a/packages/server/src/server/agent/providers/claude-agent.redesign.test.ts
+++ b/packages/server/src/server/agent/providers/claude-agent.redesign.test.ts
@@ -783,6 +783,58 @@ describe("ClaudeAgentSession redesign invariants", () => {
     }
   });
 
+  test("preserves bypass capability across query restarts triggered by thinking changes", async () => {
+    const capturedOptions: Array<{
+      permissionMode?: string;
+      allowDangerouslySkipPermissions?: boolean;
+      effort?: string;
+    }> = [];
+
+    sdkQueryFactory.mockImplementation(
+      ({
+        options,
+      }: {
+        options: {
+          permissionMode?: string;
+          allowDangerouslySkipPermissions?: boolean;
+          effort?: string;
+        };
+      }) => {
+        capturedOptions.push({
+          permissionMode: options.permissionMode,
+          allowDangerouslySkipPermissions: options.allowDangerouslySkipPermissions,
+          effort: options.effort,
+        });
+
+        return createBaseQueryMock(
+          vi.fn(async () => ({ done: true, value: undefined })),
+        );
+      },
+    );
+
+    const session = await createSession();
+
+    try {
+      await session.setMode("bypassPermissions");
+      await session.setMode("acceptEdits");
+      await session.setThinkingOption("high");
+      await session.setMode("bypassPermissions");
+
+      expect(capturedOptions).toHaveLength(2);
+      expect(capturedOptions[0]).toMatchObject({
+        permissionMode: "default",
+        allowDangerouslySkipPermissions: true,
+      });
+      expect(capturedOptions[1]).toMatchObject({
+        permissionMode: "acceptEdits",
+        allowDangerouslySkipPermissions: true,
+        effort: "high",
+      });
+    } finally {
+      await session.close();
+    }
+  });
+
   test("reuses one autonomous run for unbound stream_event bursts with no foreground run", async () => {
     const session = await createSession();
     const internal = session as unknown as {
diff --git a/packages/server/src/server/agent/providers/claude-agent.ts b/packages/server/src/server/agent/providers/claude-agent.ts
index 3cfb20299..3b05dc5db 100644
--- a/packages/server/src/server/agent/providers/claude-agent.ts
+++ b/packages/server/src/server/agent/providers/claude-agent.ts
@@ -1889,6 +1889,10 @@ class ClaudeAgentSession implements AgentSession {
       cwd: this.config.cwd,
       includePartialMessages: true,
       permissionMode: this.currentMode,
+      // Dynamic mode switching can recreate the underlying Claude query. Keep the
+      // bypass launch capability available so later setPermissionMode("bypassPermissions")
+      // calls do not fail after a model/thinking/rewind-driven restart.
+      allowDangerouslySkipPermissions: true,
       agents: this.defaults?.agents,
       canUseTool: this.handlePermissionRequest,
       ...(claudeBinary ? { pathToClaudeCodeExecutable: claudeBinary } : {}),