feat(policy): map --yolo to allowedTools wildcard policy

This PR maps the `--yolo` flag natively into a wildcard policy array
(`allowedTools: ["*"]`) and removes the concept of `ApprovalMode.YOLO` as a
distinct state in the application, fulfilling issue #11303.

This removes the hardcoded `ApprovalMode.YOLO` state and its associated
UI/bypasses. The `PolicyEngine` now evaluates YOLO purely via data-driven rules.

- Removes `ApprovalMode.YOLO`
- Removes UI toggle (`Ctrl+Y`) and indicators for YOLO
- Removes `yolo.toml`
- Updates A2A server and CLI config logic to translate YOLO into a wildcard tool
- Rewrites policy engine tests to evaluate the wildcard
- Enforces enterprise `disableYoloMode` and `secureModeEnabled` controls
  by actively preventing manual `--allowed-tools=*` bypasses.

Fixes #11303

packages/a2a-server/src/agent/task-event-driven.test.ts

@@ -9,7 +9,6 @@ import {
   type Config,
   MessageBusType,
   ToolConfirmationOutcome,
-  ApprovalMode,
   Scheduler,
   type MessageBus,
 } from '@google/gemini-cli-core';
@@ -358,7 +357,7 @@ describe('Task Event-Driven Scheduler', () => {
     // Enable YOLO mode
     const yoloConfig = createMockConfig({
       isEventDrivenSchedulerEnabled: () => true,
-      getApprovalMode: () => ApprovalMode.YOLO,
+      getAllowedTools: () => ['*'],
     }) as Config;
     const yoloMessageBus = yoloConfig.messageBus;
 

packages/a2a-server/src/agent/task.ts

@@ -10,7 +10,6 @@ import {
   type GeminiClient,
   GeminiEventType,
   ToolConfirmationOutcome,
-  ApprovalMode,
   getAllMCPServerStatuses,
   MCPServerStatus,
   isNodeError,
@@ -89,7 +88,8 @@ export class Task {
   autoExecute: boolean;
   private get isYoloMatch(): boolean {
     return (
-      this.autoExecute || this.config.getApprovalMode() === ApprovalMode.YOLO
+      this.autoExecute ||
+      (this.config.getAllowedTools()?.includes('*') ?? false)
     );
   }
 
@@ -880,9 +880,7 @@ export class Task {
     if (
       part.kind !== 'data' ||
       !part.data ||
-      // eslint-disable-next-line no-restricted-syntax
       typeof part.data['callId'] !== 'string' ||
-      // eslint-disable-next-line no-restricted-syntax
       typeof part.data['outcome'] !== 'string'
     ) {
       return false;

packages/a2a-server/src/config/config.test.ts

@@ -19,8 +19,6 @@ import {
   AuthType,
   isHeadlessMode,
   FatalAuthenticationError,
-  PolicyDecision,
-  PRIORITY_YOLO_ALLOW_ALL,
 } from '@google/gemini-cli-core';
 
 // Mock dependencies
@@ -375,35 +373,24 @@ describe('loadConfig', () => {
     });
 
     describe('YOLO mode', () => {
-      it('should enable YOLO mode and add policy rule when GEMINI_YOLO_MODE is true', async () => {
+      it('should enable wildcard allowedTools when GEMINI_YOLO_MODE is true', async () => {
         vi.stubEnv('GEMINI_YOLO_MODE', 'true');
         await loadConfig(mockSettings, mockExtensionLoader, taskId);
         expect(Config).toHaveBeenCalledWith(
           expect.objectContaining({
-            approvalMode: 'yolo',
-            policyEngineConfig: expect.objectContaining({
-              rules: expect.arrayContaining([
-                expect.objectContaining({
-                  decision: PolicyDecision.ALLOW,
-                  priority: PRIORITY_YOLO_ALLOW_ALL,
-                  modes: ['yolo'],
-                  allowRedirection: true,
-                }),
-              ]),
-            }),
+            approvalMode: 'default',
+            allowedTools: expect.arrayContaining(['*']),
           }),
         );
       });
 
-      it('should use default approval mode and empty rules when GEMINI_YOLO_MODE is not true', async () => {
+      it('should use default approval mode and undefined allowedTools when GEMINI_YOLO_MODE is not true', async () => {
         vi.stubEnv('GEMINI_YOLO_MODE', 'false');
         await loadConfig(mockSettings, mockExtensionLoader, taskId);
         expect(Config).toHaveBeenCalledWith(
           expect.objectContaining({
             approvalMode: 'default',
-            policyEngineConfig: expect.objectContaining({
-              rules: [],
-            }),
+            allowedTools: undefined,
           }),
         );
       });

packages/a2a-server/src/config/config.ts

@@ -26,8 +26,6 @@ import {
   isHeadlessMode,
   FatalAuthenticationError,
   isCloudShell,
-  PolicyDecision,
-  PRIORITY_YOLO_ALLOW_ALL,
   type TelemetryTarget,
   type ConfigParameters,
   type ExtensionLoader,
@@ -62,11 +60,6 @@ export async function loadConfig(
     }
   }
 
-  const approvalMode =
-    process.env['GEMINI_YOLO_MODE'] === 'true'
-      ? ApprovalMode.YOLO
-      : ApprovalMode.DEFAULT;
-
   const configParams: ConfigParameters = {
     sessionId: taskId,
     clientName: 'a2a-server',
@@ -79,22 +72,12 @@ export async function loadConfig(
 
     coreTools: settings.coreTools || settings.tools?.core || undefined,
     excludeTools: settings.excludeTools || settings.tools?.exclude || undefined,
-    allowedTools: settings.allowedTools || settings.tools?.allowed || undefined,
+    allowedTools:
+      process.env['GEMINI_YOLO_MODE'] === 'true'
+        ? [...(settings.allowedTools || settings.tools?.allowed || []), '*']
+        : settings.allowedTools || settings.tools?.allowed || undefined,
     showMemoryUsage: settings.showMemoryUsage || false,
-    approvalMode,
-    policyEngineConfig: {
-      rules:
-        approvalMode === ApprovalMode.YOLO
-          ? [
-              {
-                decision: PolicyDecision.ALLOW,
-                priority: PRIORITY_YOLO_ALLOW_ALL,
-                modes: [ApprovalMode.YOLO],
-                allowRedirection: true,
-              },
-            ]
-          : [],
-    },
+    approvalMode: ApprovalMode.DEFAULT,
     mcpServers: settings.mcpServers,
     cwd: workspaceDir,
     telemetry: {

packages/a2a-server/src/http/app.test.ts

@@ -72,6 +72,7 @@ const getToolRegistrySpy = vi.fn().mockReturnValue({
   getToolsByServer: vi.fn().mockReturnValue([]),
 });
 const getApprovalModeSpy = vi.fn();
+const getAllowedToolsSpy = vi.fn();
 const getShellExecutionConfigSpy = vi.fn();
 const getExtensionsSpy = vi.fn();
 
@@ -83,6 +84,7 @@ vi.mock('../config/config.js', async () => {
       const mockConfig = createMockConfig({
         getToolRegistry: getToolRegistrySpy,
         getApprovalMode: getApprovalModeSpy,
+        getAllowedTools: getAllowedToolsSpy,
         getShellExecutionConfig: getShellExecutionConfigSpy,
         getExtensions: getExtensionsSpy,
       });
@@ -118,6 +120,7 @@ describe('E2E Tests', () => {
 
   beforeEach(() => {
     getApprovalModeSpy.mockReturnValue(ApprovalMode.DEFAULT);
+    getAllowedToolsSpy.mockReturnValue([]);
   });
 
   afterAll(
@@ -406,7 +409,7 @@ describe('E2E Tests', () => {
 
   it('should handle multiple tool calls sequentially in YOLO mode', async () => {
     // Set YOLO mode to auto-approve tools and test sequential execution.
-    getApprovalModeSpy.mockReturnValue(ApprovalMode.YOLO);
+    getAllowedToolsSpy.mockReturnValue(['*']);
 
     // First call yields the tool request
     sendMessageStreamSpy.mockImplementationOnce(async function* () {
@@ -697,7 +700,7 @@ describe('E2E Tests', () => {
     });
 
     // Set approval mode to yolo
-    getApprovalModeSpy.mockReturnValue(ApprovalMode.YOLO);
+    getAllowedToolsSpy.mockReturnValue(['*']);
 
     const mockTool = new MockTool({
       name: 'test-tool-yolo',

packages/a2a-server/src/utils/testing_utils.ts

@@ -126,8 +126,8 @@ export function createMockConfig(
 
   mockConfig.getPolicyEngine = vi.fn().mockReturnValue({
     check: async () => {
-      const mode = mockConfig.getApprovalMode();
-      if (mode === ApprovalMode.YOLO) {
+      const allowed = mockConfig.getAllowedTools?.() || [];
+      if (allowed.includes('*')) {
         return { decision: PolicyDecision.ALLOW };
       }
       return { decision: PolicyDecision.ASK_USER };