revert: promote Agent Skills to stable (#17693) (#17712)

packages/cli/src/config/config.test.ts

@@ -586,7 +586,7 @@ describe('parseArguments', () => {
     process.argv = ['node', 'script.js', 'skills', 'list'];
     // Skills command enabled by default or via experimental
     const settings = createTestMergedSettings({
-      skills: { enabled: true },
+      experimental: { skills: true },
     });
     const argv = await parseArguments(settings);
     expect(argv.isCommand).toBe(true);

packages/cli/src/config/config.ts

@@ -304,7 +304,7 @@ export async function parseArguments(
     yargsInstance.command(extensionsCommand);
   }
 
-  if (settings.skills?.enabled ?? true) {
+  if (settings.experimental?.skills || (settings.skills?.enabled ?? true)) {
     yargsInstance.command(skillsCommand);
   }
   // Register hooks command if hooks are enabled
@@ -755,7 +755,8 @@ export async function loadCliConfig(
     plan: settings.experimental?.plan,
     enableEventDrivenScheduler:
       settings.experimental?.enableEventDrivenScheduler,
-    skillsSupport: settings.skills?.enabled ?? true,
+    skillsSupport:
+      settings.experimental?.skills || (settings.skills?.enabled ?? true),
     disabledSkills: settings.skills?.disabled,
     experimentalJitContext: settings.experimental?.jitContext,
     noBrowser: !!process.env['NO_BROWSER'],

packages/cli/src/config/settingsSchema.ts

@@ -1478,6 +1478,15 @@ const SETTINGS_SCHEMA = {
         description: 'Enable Just-In-Time (JIT) context loading.',
         showInDialog: false,
       },
+      skills: {
+        type: 'boolean',
+        label: 'Agent Skills',
+        category: 'Experimental',
+        requiresRestart: true,
+        default: false,
+        description: 'Enable Agent Skills (experimental).',
+        showInDialog: true,
+      },
       useOSC52Paste: {
         type: 'boolean',
         label: 'Use OSC 52 Paste',
@@ -1552,6 +1561,7 @@ const SETTINGS_SCHEMA = {
         default: true,
         description: 'Enable Agent Skills.',
         showInDialog: true,
+        ignoreInDocs: true,
       },
       disabled: {
         type: 'array',

packages/cli/src/config/skills-backward-compatibility.test.ts

@@ -0,0 +1,158 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { loadCliConfig, parseArguments } from './config.js';
+import * as trustedFolders from './trustedFolders.js';
+import { loadServerHierarchicalMemory } from '@google/gemini-cli-core';
+import { type Settings, createTestMergedSettings } from './settings.js';
+
+vi.mock('./trustedFolders.js');
+vi.mock('@google/gemini-cli-core', async (importOriginal) => {
+  const actual =
+    await importOriginal<typeof import('@google/gemini-cli-core')>();
+  return {
+    ...actual,
+    loadServerHierarchicalMemory: vi.fn(),
+    getPty: vi.fn().mockResolvedValue({ name: 'test-pty' }),
+    getVersion: vi.fn().mockResolvedValue('0.0.0-test'),
+  };
+});
+
+describe('Agent Skills Backward Compatibility', () => {
+  const originalArgv = process.argv;
+
+  beforeEach(() => {
+    vi.resetAllMocks();
+    vi.mocked(trustedFolders.isWorkspaceTrusted).mockReturnValue({
+      isTrusted: true,
+    } as unknown as trustedFolders.TrustResult);
+  });
+
+  afterEach(() => {
+    process.argv = originalArgv;
+  });
+
+  describe('loadCliConfig', () => {
+    it('should default skillsSupport to true when no settings are present', async () => {
+      vi.mocked(loadServerHierarchicalMemory).mockResolvedValue({
+        memoryContent: '',
+        fileCount: 0,
+        filePaths: [],
+      });
+
+      process.argv = ['node', 'gemini'];
+      const settings = createTestMergedSettings({});
+      const config = await loadCliConfig(
+        settings,
+        'test-session',
+        await parseArguments(settings),
+      );
+      expect(
+        (
+          config as unknown as { isSkillsSupportEnabled: () => boolean }
+        ).isSkillsSupportEnabled(),
+      ).toBe(true);
+    });
+
+    it('should prioritize skills.enabled=false from settings', async () => {
+      vi.mocked(loadServerHierarchicalMemory).mockResolvedValue({
+        memoryContent: '',
+        fileCount: 0,
+        filePaths: [],
+      });
+
+      const settings = createTestMergedSettings({
+        skills: { enabled: false },
+      } as unknown as Settings);
+
+      process.argv = ['node', 'gemini'];
+      const config = await loadCliConfig(
+        settings,
+        'test-session',
+        await parseArguments(settings),
+      );
+      expect(
+        (
+          config as unknown as { isSkillsSupportEnabled: () => boolean }
+        ).isSkillsSupportEnabled(),
+      ).toBe(false);
+    });
+
+    it('should support legacy experimental.skills=true from settings', async () => {
+      vi.mocked(loadServerHierarchicalMemory).mockResolvedValue({
+        memoryContent: '',
+        fileCount: 0,
+        filePaths: [],
+      });
+
+      const settings = createTestMergedSettings({
+        experimental: { skills: true },
+      } as unknown as Settings);
+
+      process.argv = ['node', 'gemini'];
+      const config = await loadCliConfig(
+        settings,
+        'test-session',
+        await parseArguments(settings),
+      );
+      expect(
+        (
+          config as unknown as { isSkillsSupportEnabled: () => boolean }
+        ).isSkillsSupportEnabled(),
+      ).toBe(true);
+    });
+
+    it('should prioritize legacy experimental.skills=true over new skills.enabled=false', async () => {
+      vi.mocked(loadServerHierarchicalMemory).mockResolvedValue({
+        memoryContent: '',
+        fileCount: 0,
+        filePaths: [],
+      });
+
+      const settings = createTestMergedSettings({
+        skills: { enabled: false },
+        experimental: { skills: true },
+      } as unknown as Settings);
+
+      process.argv = ['node', 'gemini'];
+      const config = await loadCliConfig(
+        settings,
+        'test-session',
+        await parseArguments(settings),
+      );
+      expect(
+        (
+          config as unknown as { isSkillsSupportEnabled: () => boolean }
+        ).isSkillsSupportEnabled(),
+      ).toBe(true);
+    });
+
+    it('should still be enabled by default if legacy experimental.skills is false (since new default is true)', async () => {
+      vi.mocked(loadServerHierarchicalMemory).mockResolvedValue({
+        memoryContent: '',
+        fileCount: 0,
+        filePaths: [],
+      });
+
+      const settings = createTestMergedSettings({
+        experimental: { skills: false },
+      } as unknown as Settings);
+
+      process.argv = ['node', 'gemini'];
+      const config = await loadCliConfig(
+        settings,
+        'test-session',
+        await parseArguments(settings),
+      );
+      expect(
+        (
+          config as unknown as { isSkillsSupportEnabled: () => boolean }
+        ).isSkillsSupportEnabled(),
+      ).toBe(true);
+    });
+  });
+});

packages/cli/src/services/BuiltinCommandLoader.test.ts

@@ -119,12 +119,11 @@ describe('BuiltinCommandLoader', () => {
       getEnableHooks: () => false,
       getEnableHooksUI: () => false,
       getExtensionsEnabled: vi.fn().mockReturnValue(true),
-      isSkillsSupportEnabled: vi.fn().mockReturnValue(true),
+      isSkillsSupportEnabled: vi.fn().mockReturnValue(false),
       isAgentsEnabled: vi.fn().mockReturnValue(false),
       getMcpEnabled: vi.fn().mockReturnValue(true),
       getSkillManager: vi.fn().mockReturnValue({
         getAllSkills: vi.fn().mockReturnValue([]),
-        isAdminEnabled: vi.fn().mockReturnValue(true),
       }),
     } as unknown as Config;
 
@@ -261,12 +260,11 @@ describe('BuiltinCommandLoader profile', () => {
       getEnableHooks: () => false,
       getEnableHooksUI: () => false,
       getExtensionsEnabled: vi.fn().mockReturnValue(true),
-      isSkillsSupportEnabled: vi.fn().mockReturnValue(true),
+      isSkillsSupportEnabled: vi.fn().mockReturnValue(false),
       isAgentsEnabled: vi.fn().mockReturnValue(false),
       getMcpEnabled: vi.fn().mockReturnValue(true),
       getSkillManager: vi.fn().mockReturnValue({
         getAllSkills: vi.fn().mockReturnValue([]),
-        isAdminEnabled: vi.fn().mockReturnValue(true),
       }),
     } as unknown as Config;
   });