fix(agent): make Auto Mode auto-approve edits and shell commands (#2970)

Author: posthog[bot]

packages/agent/src/adapters/claude/permissions/permission-handlers.test.ts

@@ -345,3 +345,50 @@ describe("canUseTool MCP approval enforcement", () => {
     );
   });
 });
+
+describe("canUseTool auto mode hands-off approval", () => {
+  beforeEach(() => {
+    clearMcpToolMetadataCache();
+  });
+
+  // Auto mode advertises hands-off approval; it must not prompt for the write
+  // and shell tools that drive every real task.
+  it.each(["Bash", "BashOutput", "KillShell", "Edit", "Write", "NotebookEdit"])(
+    "auto-allows %s in auto mode without prompting",
+    async (toolName) => {
+      const context = createContext(toolName, {
+        session: {
+          permissionMode: "auto",
+          settingsManager: {
+            getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          },
+        },
+      });
+
+      const result = await canUseTool(context);
+
+      expect(result.behavior).toBe("allow");
+      expect(context.client.requestPermission).not.toHaveBeenCalled();
+    },
+  );
+
+  // Guard against the fix leaking into default mode, where these tools should
+  // still go through the manual permission prompt.
+  it.each(["Bash", "Edit", "Write"])(
+    "still prompts for %s in default mode",
+    async (toolName) => {
+      const context = createContext(toolName, {
+        session: {
+          permissionMode: "default",
+          settingsManager: {
+            getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          },
+        },
+      });
+
+      await canUseTool(context);
+
+      expect(context.client.requestPermission).toHaveBeenCalled();
+    },
+  );
+});

packages/agent/src/adapters/claude/tools.ts

@@ -43,7 +43,13 @@ const BASE_ALLOWED_TOOLS = [
 ];
 
 const AUTO_ALLOWED_TOOLS: Record<string, Set<string>> = {
-  auto: new Set(BASE_ALLOWED_TOOLS),
+  // Auto mode is hands-off: it auto-approves file edits and shell commands on
+  // top of the base read/search/web/agent tools. Without WRITE_TOOLS and
+  // BASH_TOOLS here, Edit/Write/Bash fall through to a manual prompt on every
+  // call, which contradicts what the mode advertises. MCP tools are still gated
+  // separately (do_not_use is denied, needs_approval still prompts) in
+  // canUseTool, so auto stays narrower than bypassPermissions.
+  auto: new Set([...BASE_ALLOWED_TOOLS, ...WRITE_TOOLS, ...BASH_TOOLS]),
   default: new Set(BASE_ALLOWED_TOOLS),
   acceptEdits: new Set([...BASE_ALLOWED_TOOLS, ...WRITE_TOOLS]),
   plan: new Set(BASE_ALLOWED_TOOLS),

packages/agent/src/execution-mode.ts

@@ -35,7 +35,7 @@ if (ALLOW_BYPASS) {
     {
       id: "auto",
       name: "Auto Mode",
-      description: "Use a model classifier to approve/deny permission prompts",
+      description: "Auto-approve file edits and shell commands",
     },
   );
 }

packages/core/src/sessions/executionModes.ts

@@ -30,7 +30,7 @@ const availableModes: ModeInfo[] = [
   {
     id: "auto",
     name: "Auto Mode",
-    description: "Use a model classifier to approve/deny permission prompts",
+    description: "Auto-approve file edits and shell commands",
   },
 ];