Merge branch 'main' into issue-17132-env-compat-warning

evals/grep_search_functionality.eval.ts

@@ -0,0 +1,170 @@
+/**
+ * @license
+ * Copyright 202 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, expect } from 'vitest';
+import { evalTest, TestRig } from './test-helper.js';
+import {
+  assertModelHasOutput,
+  checkModelOutputContent,
+} from './test-helper.js';
+
+describe('grep_search_functionality', () => {
+  const TEST_PREFIX = 'Grep Search Functionality: ';
+
+  evalTest('USUALLY_PASSES', {
+    name: 'should find a simple string in a file',
+    files: {
+      'test.txt': `hello
+    world
+    hello world`,
+    },
+    prompt: 'Find "world" in test.txt',
+    assert: async (rig: TestRig, result: string) => {
+      await rig.waitForToolCall('grep_search');
+      assertModelHasOutput(result);
+      checkModelOutputContent(result, {
+        expectedContent: [/L2: world/, /L3: hello world/],
+        testName: `${TEST_PREFIX}simple search`,
+      });
+    },
+  });
+
+  evalTest('USUALLY_PASSES', {
+    name: 'should perform a case-sensitive search',
+    files: {
+      'test.txt': `Hello
+    hello`,
+    },
+    prompt: 'Find "Hello" in test.txt, case-sensitively.',
+    assert: async (rig: TestRig, result: string) => {
+      const wasToolCalled = await rig.waitForToolCall(
+        'grep_search',
+        undefined,
+        (args) => {
+          const params = JSON.parse(args);
+          return params.case_sensitive === true;
+        },
+      );
+      expect(
+        wasToolCalled,
+        'Expected grep_search to be called with case_sensitive: true',
+      ).toBe(true);
+
+      assertModelHasOutput(result);
+      checkModelOutputContent(result, {
+        expectedContent: [/L1: Hello/],
+        forbiddenContent: [/L2: hello/],
+        testName: `${TEST_PREFIX}case-sensitive search`,
+      });
+    },
+  });
+
+  evalTest('USUALLY_PASSES', {
+    name: 'should return only file names when names_only is used',
+    files: {
+      'file1.txt': 'match me',
+      'file2.txt': 'match me',
+    },
+    prompt: 'Find the files containing "match me".',
+    assert: async (rig: TestRig, result: string) => {
+      const wasToolCalled = await rig.waitForToolCall(
+        'grep_search',
+        undefined,
+        (args) => {
+          const params = JSON.parse(args);
+          return params.names_only === true;
+        },
+      );
+      expect(
+        wasToolCalled,
+        'Expected grep_search to be called with names_only: true',
+      ).toBe(true);
+
+      assertModelHasOutput(result);
+      checkModelOutputContent(result, {
+        expectedContent: [/file1.txt/, /file2.txt/],
+        forbiddenContent: [/L1:/],
+        testName: `${TEST_PREFIX}names_only search`,
+      });
+    },
+  });
+
+  evalTest('USUALLY_PASSES', {
+    name: 'should search only within the specified include glob',
+    files: {
+      'file.js': 'my_function();',
+      'file.ts': 'my_function();',
+    },
+    prompt: 'Find "my_function" in .js files.',
+    assert: async (rig: TestRig, result: string) => {
+      const wasToolCalled = await rig.waitForToolCall(
+        'grep_search',
+        undefined,
+        (args) => {
+          const params = JSON.parse(args);
+          return params.include === '*.js';
+        },
+      );
+      expect(
+        wasToolCalled,
+        'Expected grep_search to be called with include: "*.js"',
+      ).toBe(true);
+
+      assertModelHasOutput(result);
+      checkModelOutputContent(result, {
+        expectedContent: [/file.js/],
+        forbiddenContent: [/file.ts/],
+        testName: `${TEST_PREFIX}include glob search`,
+      });
+    },
+  });
+
+  evalTest('USUALLY_PASSES', {
+    name: 'should search within a specific subdirectory',
+    files: {
+      'src/main.js': 'unique_string_1',
+      'lib/main.js': 'unique_string_2',
+    },
+    prompt: 'Find "unique_string" in the src directory.',
+    assert: async (rig: TestRig, result: string) => {
+      const wasToolCalled = await rig.waitForToolCall(
+        'grep_search',
+        undefined,
+        (args) => {
+          const params = JSON.parse(args);
+          return params.dir_path === 'src';
+        },
+      );
+      expect(
+        wasToolCalled,
+        'Expected grep_search to be called with dir_path: "src"',
+      ).toBe(true);
+
+      assertModelHasOutput(result);
+      checkModelOutputContent(result, {
+        expectedContent: [/unique_string_1/],
+        forbiddenContent: [/unique_string_2/],
+        testName: `${TEST_PREFIX}subdirectory search`,
+      });
+    },
+  });
+
+  evalTest('USUALLY_PASSES', {
+    name: 'should report no matches correctly',
+    files: {
+      'file.txt': 'nothing to see here',
+    },
+    prompt: 'Find "nonexistent" in file.txt',
+    assert: async (rig: TestRig, result: string) => {
+      await rig.waitForToolCall('grep_search');
+      assertModelHasOutput(result);
+      checkModelOutputContent(result, {
+        expectedContent: [/No matches found/],
+        testName: `${TEST_PREFIX}no matches`,
+      });
+    },
+  });
+});

integration-tests/concurrency-limit.responses

@@ -0,0 +1,12 @@
+{"method":"generateContentStream","response":[{"candidates":[{"content":{"parts":[{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/1"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/2"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/3"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/4"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/5"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/6"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/7"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/8"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/9"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/10"}}},{"functionCall":{"name":"web_fetch","args":{"prompt":"fetch https://example.com/11"}}}],"role":"model"},"finishReason":"STOP","index":0}],"usageMetadata":{"promptTokenCount":100,"candidatesTokenCount":500,"totalTokenCount":600}}]}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 1 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 2 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 3 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 4 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 5 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 6 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 7 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 8 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 9 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContent","response":{"candidates":[{"content":{"parts":[{"text":"Page 10 content"}],"role":"model"},"finishReason":"STOP","index":0}]}}
+{"method":"generateContentStream","response":[{"candidates":[{"content":{"parts":[{"text":"Some requests were rate limited: Rate limit exceeded for host. Please wait 60 seconds before trying again."}],"role":"model"},"finishReason":"STOP","index":0}],"usageMetadata":{"promptTokenCount":1000,"candidatesTokenCount":50,"totalTokenCount":1050}}]}

integration-tests/concurrency-limit.test.ts

@@ -0,0 +1,48 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { TestRig } from './test-helper.js';
+import { join } from 'node:path';
+
+describe('web-fetch rate limiting', () => {
+  let rig: TestRig;
+
+  beforeEach(() => {
+    rig = new TestRig();
+  });
+
+  afterEach(async () => {
+    if (rig) {
+      await rig.cleanup();
+    }
+  });
+
+  it('should rate limit multiple requests to the same host', async () => {
+    rig.setup('web-fetch rate limit', {
+      settings: { tools: { core: ['web_fetch'] } },
+      fakeResponsesPath: join(
+        import.meta.dirname,
+        'concurrency-limit.responses',
+      ),
+    });
+
+    const result = await rig.run({
+      args: `Fetch 11 pages from example.com`,
+    });
+
+    // We expect to find at least one tool call that failed with a rate limit error.
+    const toolLogs = rig.readToolLogs();
+    const rateLimitedCalls = toolLogs.filter(
+      (log) =>
+        log.toolRequest.name === 'web_fetch' &&
+        log.toolRequest.error?.includes('Rate limit exceeded'),
+    );
+
+    expect(rateLimitedCalls.length).toBeGreaterThan(0);
+    expect(result).toContain('Rate limit exceeded');
+  });
+});

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

@@ -224,4 +224,59 @@ describe('ExtensionRegistryClient', () => {
       'Failed to fetch extensions: Not Found',
     );
   });
+
+  it('should not return irrelevant results', async () => {
+    fetchMock.mockResolvedValue({
+      ok: true,
+      json: async () => [
+        ...mockExtensions,
+        {
+          id: 'dataplex',
+          extensionName: 'dataplex',
+          extensionDescription: 'Connect to Dataplex Universal Catalog...',
+          fullName: 'google-cloud/dataplex',
+          rank: 6,
+          stars: 6,
+          url: '',
+          repoDescription: '',
+          lastUpdated: '',
+          extensionVersion: '1.0.0',
+          avatarUrl: '',
+          hasMCP: false,
+          hasContext: false,
+          isGoogleOwned: true,
+          licenseKey: '',
+          hasHooks: false,
+          hasCustomCommands: false,
+          hasSkills: false,
+        },
+        {
+          id: 'conductor',
+          extensionName: 'conductor',
+          extensionDescription: 'A conductor extension that actually matches.',
+          fullName: 'someone/conductor',
+          rank: 100,
+          stars: 100,
+          url: '',
+          repoDescription: '',
+          lastUpdated: '',
+          extensionVersion: '1.0.0',
+          avatarUrl: '',
+          hasMCP: false,
+          hasContext: false,
+          isGoogleOwned: false,
+          licenseKey: '',
+          hasHooks: false,
+          hasCustomCommands: false,
+          hasSkills: false,
+        },
+      ],
+    });
+
+    const results = await client.searchExtensions('conductor');
+    const ids = results.map((r) => r.id);
+
+    expect(ids).not.toContain('dataplex');
+    expect(ids).toContain('conductor');
+  });
 });

packages/cli/src/config/extensionRegistryClient.ts

@@ -79,7 +79,7 @@ export class ExtensionRegistryClient {
     const fzf = new AsyncFzf(allExtensions, {
       selector: (ext: RegistryExtension) =>
         `${ext.extensionName} ${ext.extensionDescription} ${ext.fullName}`,
-      fuzzy: 'v2',
+      fuzzy: true,
     });
     const results = await fzf.find(query);
     return results.map((r: { item: RegistryExtension }) => r.item);
@@ -108,7 +108,6 @@ export class ExtensionRegistryClient {
         // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
         return (await response.json()) as RegistryExtension[];
       } catch (error) {
-        // Clear the promise on failure so that subsequent calls can try again
         ExtensionRegistryClient.fetchPromise = null;
         throw error;
       }

packages/cli/src/ui/commands/extensionsCommand.ts

@@ -20,6 +20,7 @@ import {
 import {
   type CommandContext,
   type SlashCommand,
+  type SlashCommandActionReturn,
   CommandKind,
 } from './types.js';
 import open from 'open';
@@ -35,6 +36,7 @@ import { stat } from 'node:fs/promises';
 import { ExtensionSettingScope } from '../../config/extensions/extensionSettings.js';
 import { type ConfigLogger } from '../../commands/extensions/utils.js';
 import { ConfigExtensionDialog } from '../components/ConfigExtensionDialog.js';
+import { ExtensionRegistryView } from '../components/views/ExtensionRegistryView.js';
 import React from 'react';
 
 function showMessageIfNoExtensions(
@@ -265,7 +267,28 @@ async function restartAction(
   }
 }
 
-async function exploreAction(context: CommandContext) {
+async function exploreAction(
+  context: CommandContext,
+): Promise<SlashCommandActionReturn | void> {
+  const settings = context.services.settings.merged;
+  const useRegistryUI = settings.experimental?.extensionRegistry;
+
+  if (useRegistryUI) {
+    const extensionManager = context.services.config?.getExtensionLoader();
+    if (extensionManager instanceof ExtensionManager) {
+      return {
+        type: 'custom_dialog' as const,
+        component: React.createElement(ExtensionRegistryView, {
+          onSelect: (extension) => {
+            debugLogger.debug(`Selected extension: ${extension.extensionName}`);
+          },
+          onClose: () => context.ui.removeComponent(),
+          extensionManager,
+        }),
+      };
+    }
+  }
+
   const extensionsUrl = 'https://geminicli.com/extensions/';
 
   // Only check for NODE_ENV for explicit test mode, not for unit test framework

packages/cli/src/ui/components/shared/SearchableList.test.tsx

@@ -0,0 +1,233 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import React from 'react';
+import { render } from '../../../test-utils/render.js';
+import { waitFor } from '../../../test-utils/async.js';
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import {
+  SearchableList,
+  type SearchableListProps,
+  type SearchListState,
+  type GenericListItem,
+} from './SearchableList.js';
+import { KeypressProvider } from '../../contexts/KeypressContext.js';
+import { useTextBuffer } from './text-buffer.js';
+
+const useMockSearch = (props: {
+  items: GenericListItem[];
+  initialQuery?: string;
+  onSearch?: (query: string) => void;
+}): SearchListState<GenericListItem> => {
+  const { onSearch, items, initialQuery = '' } = props;
+  const [text, setText] = React.useState(initialQuery);
+  const filteredItems = React.useMemo(
+    () =>
+      items.filter((item: GenericListItem) =>
+        item.label.toLowerCase().includes(text.toLowerCase()),
+      ),
+    [items, text],
+  );
+
+  React.useEffect(() => {
+    onSearch?.(text);
+  }, [text, onSearch]);
+
+  const searchBuffer = useTextBuffer({
+    initialText: text,
+    onChange: setText,
+    viewport: { width: 100, height: 1 },
+    singleLine: true,
+  });
+
+  return {
+    filteredItems,
+    searchBuffer,
+    searchQuery: text,
+    setSearchQuery: setText,
+    maxLabelWidth: 10,
+  };
+};
+
+vi.mock('../../contexts/UIStateContext.js', () => ({
+  useUIState: () => ({
+    mainAreaWidth: 100,
+  }),
+}));
+
+const mockItems: GenericListItem[] = [
+  {
+    key: 'item-1',
+    label: 'Item One',
+    description: 'Description for item one',
+  },
+  {
+    key: 'item-2',
+    label: 'Item Two',
+    description: 'Description for item two',
+  },
+  {
+    key: 'item-3',
+    label: 'Item Three',
+    description: 'Description for item three',
+  },
+];
+
+describe('SearchableList', () => {
+  let mockOnSelect: ReturnType<typeof vi.fn>;
+  let mockOnClose: ReturnType<typeof vi.fn>;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockOnSelect = vi.fn();
+    mockOnClose = vi.fn();
+  });
+
+  const renderList = (
+    props: Partial<SearchableListProps<GenericListItem>> = {},
+  ) => {
+    const defaultProps: SearchableListProps<GenericListItem> = {
+      title: 'Test List',
+      items: mockItems,
+      onSelect: mockOnSelect,
+      onClose: mockOnClose,
+      useSearch: useMockSearch,
+      ...props,
+    };
+
+    return render(
+      <KeypressProvider>
+        <SearchableList {...defaultProps} />
+      </KeypressProvider>,
+    );
+  };
+
+  it('should render all items initially', async () => {
+    const { lastFrame, waitUntilReady } = renderList();
+    await waitUntilReady();
+    const frame = lastFrame();
+
+    expect(frame).toContain('Test List');
+
+    expect(frame).toContain('Item One');
+    expect(frame).toContain('Item Two');
+    expect(frame).toContain('Item Three');
+
+    expect(frame).toContain('Description for item one');
+  });
+
+  it('should reset selection to top when items change if resetSelectionOnItemsChange is true', async () => {
+    const { lastFrame, stdin, waitUntilReady } = renderList({
+      resetSelectionOnItemsChange: true,
+    });
+    await waitUntilReady();
+
+    await React.act(async () => {
+      stdin.write('\u001B[B'); // Down arrow
+    });
+
+    await waitFor(() => {
+      const frame = lastFrame();
+      expect(frame).toContain('> Item Two');
+    });
+
+    await React.act(async () => {
+      stdin.write('One');
+    });
+
+    await waitFor(() => {
+      const frame = lastFrame();
+      expect(frame).toContain('Item One');
+      expect(frame).not.toContain('Item Two');
+    });
+
+    await React.act(async () => {
+      // Backspace "One" (3 chars)
+      stdin.write('\u007F\u007F\u007F');
+    });
+
+    await waitFor(() => {
+      const frame = lastFrame();
+      expect(frame).toContain('Item Two');
+      expect(frame).toContain('> Item One');
+      expect(frame).not.toContain('> Item Two');
+    });
+  });
+
+  it('should filter items based on search query', async () => {
+    const { lastFrame, stdin } = renderList();
+
+    await React.act(async () => {
+      stdin.write('Two');
+    });
+
+    await waitFor(() => {
+      const frame = lastFrame();
+      expect(frame).toContain('Item Two');
+      expect(frame).not.toContain('Item One');
+      expect(frame).not.toContain('Item Three');
+    });
+  });
+
+  it('should show "No items found." when no items match', async () => {
+    const { lastFrame, stdin } = renderList();
+
+    await React.act(async () => {
+      stdin.write('xyz123');
+    });
+
+    await waitFor(() => {
+      const frame = lastFrame();
+      expect(frame).toContain('No items found.');
+    });
+  });
+
+  it('should handle selection with Enter', async () => {
+    const { stdin } = renderList();
+
+    await React.act(async () => {
+      stdin.write('\r'); // Enter
+    });
+
+    await waitFor(() => {
+      expect(mockOnSelect).toHaveBeenCalledWith(mockItems[0]);
+    });
+  });
+
+  it('should handle navigation and selection', async () => {
+    const { stdin } = renderList();
+
+    await React.act(async () => {
+      stdin.write('\u001B[B'); // Down arrow
+    });
+
+    await React.act(async () => {
+      stdin.write('\r'); // Enter
+    });
+
+    await waitFor(() => {
+      expect(mockOnSelect).toHaveBeenCalledWith(mockItems[1]);
+    });
+  });
+
+  it('should handle close with Esc', async () => {
+    const { stdin } = renderList();
+
+    await React.act(async () => {
+      stdin.write('\u001B'); // Esc
+    });
+
+    await waitFor(() => {
+      expect(mockOnClose).toHaveBeenCalled();
+    });
+  });
+
+  it('should match snapshot', async () => {
+    const { lastFrame, waitUntilReady } = renderList();
+    await waitUntilReady();
+    expect(lastFrame()).toMatchSnapshot();
+  });
+});

packages/cli/src/ui/components/shared/SearchableList.tsx

@@ -0,0 +1,231 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import React, { useMemo, useCallback } from 'react';
+import { Box, Text } from 'ink';
+import { theme } from '../../semantic-colors.js';
+import { useSelectionList } from '../../hooks/useSelectionList.js';
+import { TextInput } from './TextInput.js';
+import type { TextBuffer } from './text-buffer.js';
+import { useKeypress } from '../../hooks/useKeypress.js';
+import { keyMatchers, Command } from '../../keyMatchers.js';
+
+/**
+ * Generic interface for items in a searchable list.
+ */
+export interface GenericListItem {
+  key: string;
+  label: string;
+  description?: string;
+  [key: string]: unknown;
+}
+
+/**
+ * State returned by the search hook.
+ */
+export interface SearchListState<T extends GenericListItem> {
+  filteredItems: T[];
+  searchBuffer: TextBuffer | undefined;
+  searchQuery: string;
+  setSearchQuery: (query: string) => void;
+  maxLabelWidth: number;
+}
+
+/**
+ * Props for the SearchableList component.
+ */
+export interface SearchableListProps<T extends GenericListItem> {
+  title?: string;
+  items: T[];
+  onSelect: (item: T) => void;
+  onClose: () => void;
+  searchPlaceholder?: string;
+  /** Custom item renderer */
+  renderItem?: (
+    item: T,
+    isActive: boolean,
+    labelWidth: number,
+  ) => React.ReactNode;
+  /** Optional header content */
+  header?: React.ReactNode;
+  /** Optional footer content */
+  footer?: (info: {
+    startIndex: number;
+    endIndex: number;
+    totalVisible: number;
+  }) => React.ReactNode;
+  maxItemsToShow?: number;
+  /** Hook to handle search logic */
+  useSearch: (props: {
+    items: T[];
+    onSearch?: (query: string) => void;
+  }) => SearchListState<T>;
+  onSearch?: (query: string) => void;
+  /** Whether to reset selection to the top when items change (e.g. after search) */
+  resetSelectionOnItemsChange?: boolean;
+}
+
+/**
+ * A generic searchable list component with keyboard navigation.
+ */
+export function SearchableList<T extends GenericListItem>({
+  title,
+  items,
+  onSelect,
+  onClose,
+  searchPlaceholder = 'Search...',
+  renderItem,
+  header,
+  footer,
+  maxItemsToShow = 10,
+  useSearch,
+  onSearch,
+  resetSelectionOnItemsChange = false,
+}: SearchableListProps<T>): React.JSX.Element {
+  const { filteredItems, searchBuffer, maxLabelWidth } = useSearch({
+    items,
+    onSearch,
+  });
+
+  const selectionItems = useMemo(
+    () =>
+      filteredItems.map((item) => ({
+        key: item.key,
+        value: item,
+      })),
+    [filteredItems],
+  );
+
+  const handleSelectValue = useCallback(
+    (item: T) => {
+      onSelect(item);
+    },
+    [onSelect],
+  );
+
+  const { activeIndex, setActiveIndex } = useSelectionList({
+    items: selectionItems,
+    onSelect: handleSelectValue,
+    isFocused: true,
+    showNumbers: false,
+    wrapAround: true,
+  });
+
+  // Reset selection to top when items change if requested
+  const prevItemsRef = React.useRef(filteredItems);
+  React.useEffect(() => {
+    if (resetSelectionOnItemsChange && filteredItems !== prevItemsRef.current) {
+      setActiveIndex(0);
+    }
+    prevItemsRef.current = filteredItems;
+  }, [filteredItems, setActiveIndex, resetSelectionOnItemsChange]);
+
+  // Handle global Escape key to close the list
+  useKeypress(
+    (key) => {
+      if (keyMatchers[Command.ESCAPE](key)) {
+        onClose();
+        return true;
+      }
+      return false;
+    },
+    { isActive: true },
+  );
+
+  const scrollOffset = Math.max(
+    0,
+    Math.min(
+      activeIndex - Math.floor(maxItemsToShow / 2),
+      Math.max(0, filteredItems.length - maxItemsToShow),
+    ),
+  );
+
+  const visibleItems = filteredItems.slice(
+    scrollOffset,
+    scrollOffset + maxItemsToShow,
+  );
+
+  const defaultRenderItem = (
+    item: T,
+    isActive: boolean,
+    labelWidth: number,
+  ) => (
+    <Box flexDirection="column">
+      <Text
+        color={isActive ? theme.status.success : theme.text.primary}
+        bold={isActive}
+      >
+        {isActive ? '> ' : '  '}
+        {item.label.padEnd(labelWidth)}
+      </Text>
+      {item.description && (
+        <Box marginLeft={2}>
+          <Text color={theme.text.secondary} wrap="truncate-end">
+            {item.description}
+          </Text>
+        </Box>
+      )}
+    </Box>
+  );
+
+  return (
+    <Box flexDirection="column" width="100%" height="100%" paddingX={1}>
+      {title && (
+        <Box marginBottom={1}>
+          <Text bold color={theme.text.primary}>
+            {title}
+          </Text>
+        </Box>
+      )}
+
+      {searchBuffer && (
+        <Box
+          borderStyle="round"
+          borderColor={theme.border.default}
+          paddingX={1}
+          marginBottom={1}
+        >
+          <TextInput
+            buffer={searchBuffer}
+            placeholder={searchPlaceholder}
+            focus={true}
+          />
+        </Box>
+      )}
+
+      {header && <Box marginBottom={1}>{header}</Box>}
+
+      <Box flexDirection="column" flexGrow={1}>
+        {filteredItems.length === 0 ? (
+          <Box marginX={2}>
+            <Text color={theme.text.secondary}>No items found.</Text>
+          </Box>
+        ) : (
+          visibleItems.map((item, index) => {
+            const isSelected = activeIndex === scrollOffset + index;
+            return (
+              <Box key={item.key} marginBottom={1}>
+                {renderItem
+                  ? renderItem(item, isSelected, maxLabelWidth)
+                  : defaultRenderItem(item, isSelected, maxLabelWidth)}
+              </Box>
+            );
+          })
+        )}
+      </Box>
+
+      {footer && (
+        <Box marginTop={1}>
+          {footer({
+            startIndex: scrollOffset,
+            endIndex: scrollOffset + visibleItems.length,
+            totalVisible: filteredItems.length,
+          })}
+        </Box>
+      )}
+    </Box>
+  );
+}

packages/cli/src/ui/components/shared/__snapshots__/SearchableList.test.tsx.snap

@@ -0,0 +1,19 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`SearchableList > should match snapshot 1`] = `
+" Test List
+
+ ╭────────────────────────────────────────────────────────────────────────────────────────────────╮
+ │ Search...                                                                                      │
+ ╰────────────────────────────────────────────────────────────────────────────────────────────────╯
+
+ > Item One
+   Description for item one
+
+   Item Two
+   Description for item two
+
+   Item Three
+   Description for item three
+"
+`;

packages/cli/src/ui/components/views/ExtensionRegistryView.test.tsx

@@ -0,0 +1,204 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import React from 'react';
+import { render } from '../../../test-utils/render.js';
+import { waitFor } from '../../../test-utils/async.js';
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { ExtensionRegistryView } from './ExtensionRegistryView.js';
+import { type ExtensionManager } from '../../../config/extension-manager.js';
+import { useExtensionRegistry } from '../../hooks/useExtensionRegistry.js';
+import { useExtensionUpdates } from '../../hooks/useExtensionUpdates.js';
+import { useRegistrySearch } from '../../hooks/useRegistrySearch.js';
+import { type RegistryExtension } from '../../../config/extensionRegistryClient.js';
+import { useUIState } from '../../contexts/UIStateContext.js';
+import { useConfig } from '../../contexts/ConfigContext.js';
+import { KeypressProvider } from '../../contexts/KeypressContext.js';
+import {
+  type SearchListState,
+  type GenericListItem,
+} from '../shared/SearchableList.js';
+import { type TextBuffer } from '../shared/text-buffer.js';
+
+// Mocks
+vi.mock('../../hooks/useExtensionRegistry.js');
+vi.mock('../../hooks/useExtensionUpdates.js');
+vi.mock('../../hooks/useRegistrySearch.js');
+vi.mock('../../../config/extension-manager.js');
+vi.mock('../../contexts/UIStateContext.js');
+vi.mock('../../contexts/ConfigContext.js');
+
+const mockExtensions: RegistryExtension[] = [
+  {
+    id: 'ext1',
+    extensionName: 'Test Extension 1',
+    extensionDescription: 'Description 1',
+    fullName: 'author/ext1',
+    extensionVersion: '1.0.0',
+    rank: 1,
+    stars: 10,
+    url: 'http://example.com',
+    repoDescription: 'Repo Desc 1',
+    avatarUrl: 'http://avatar.com',
+    lastUpdated: '2023-01-01',
+    hasMCP: false,
+    hasContext: false,
+    hasHooks: false,
+    hasSkills: false,
+    hasCustomCommands: false,
+    isGoogleOwned: false,
+    licenseKey: 'mit',
+  },
+  {
+    id: 'ext2',
+    extensionName: 'Test Extension 2',
+    extensionDescription: 'Description 2',
+    fullName: 'author/ext2',
+    extensionVersion: '2.0.0',
+    rank: 2,
+    stars: 20,
+    url: 'http://example.com/2',
+    repoDescription: 'Repo Desc 2',
+    avatarUrl: 'http://avatar.com/2',
+    lastUpdated: '2023-01-02',
+    hasMCP: true,
+    hasContext: true,
+    hasHooks: true,
+    hasSkills: true,
+    hasCustomCommands: true,
+    isGoogleOwned: true,
+    licenseKey: 'apache-2.0',
+  },
+];
+
+describe('ExtensionRegistryView', () => {
+  let mockExtensionManager: ExtensionManager;
+  let mockOnSelect: ReturnType<typeof vi.fn>;
+  let mockOnClose: ReturnType<typeof vi.fn>;
+  let mockSearch: ReturnType<typeof vi.fn>;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+
+    mockExtensionManager = {
+      getExtensions: vi.fn().mockReturnValue([]),
+    } as unknown as ExtensionManager;
+
+    mockOnSelect = vi.fn();
+    mockOnClose = vi.fn();
+    mockSearch = vi.fn();
+
+    vi.mocked(useExtensionRegistry).mockReturnValue({
+      extensions: mockExtensions,
+      loading: false,
+      error: null,
+      search: mockSearch,
+    });
+
+    vi.mocked(useExtensionUpdates).mockReturnValue({
+      extensionsUpdateState: new Map(),
+    } as unknown as ReturnType<typeof useExtensionUpdates>);
+
+    // Mock useRegistrySearch implementation
+    vi.mocked(useRegistrySearch).mockImplementation(
+      (props: { items: GenericListItem[]; onSearch?: (q: string) => void }) =>
+        ({
+          filteredItems: props.items, // Pass through items
+          searchBuffer: {
+            text: '',
+            cursorOffset: 0,
+            viewport: { width: 10, height: 1 },
+            visualCursor: [0, 0] as [number, number],
+            viewportVisualLines: [{ text: '', visualRowIndex: 0 }],
+            visualScrollRow: 0,
+            lines: [''],
+            cursor: [0, 0] as [number, number],
+            selectionAnchor: undefined,
+          } as unknown as TextBuffer,
+          searchQuery: '',
+          setSearchQuery: vi.fn(),
+          maxLabelWidth: 10,
+        }) as unknown as SearchListState<GenericListItem>,
+    );
+
+    vi.mocked(useUIState).mockReturnValue({
+      mainAreaWidth: 100,
+    } as unknown as ReturnType<typeof useUIState>);
+
+    vi.mocked(useConfig).mockReturnValue({
+      getEnableExtensionReloading: vi.fn().mockReturnValue(false),
+    } as unknown as ReturnType<typeof useConfig>);
+  });
+
+  const renderView = () =>
+    render(
+      <KeypressProvider>
+        <ExtensionRegistryView
+          extensionManager={mockExtensionManager}
+          onSelect={mockOnSelect}
+          onClose={mockOnClose}
+        />
+      </KeypressProvider>,
+    );
+
+  it('should render extensions', async () => {
+    const { lastFrame } = renderView();
+    await waitFor(() => {
+      expect(lastFrame()).toContain('Test Extension 1');
+      expect(lastFrame()).toContain('Test Extension 2');
+    });
+  });
+
+  it('should use useRegistrySearch hook', () => {
+    renderView();
+    expect(useRegistrySearch).toHaveBeenCalled();
+  });
+
+  it('should call search function when typing', async () => {
+    // Mock useRegistrySearch to trigger onSearch
+    vi.mocked(useRegistrySearch).mockImplementation(
+      (props: {
+        items: GenericListItem[];
+        onSearch?: (q: string) => void;
+      }): SearchListState<GenericListItem> => {
+        const { onSearch } = props;
+        // Simulate typing
+        React.useEffect(() => {
+          if (onSearch) {
+            onSearch('test query');
+          }
+        }, [onSearch]);
+        return {
+          filteredItems: props.items,
+          searchBuffer: {
+            text: 'test query',
+            cursorOffset: 10,
+            viewport: { width: 10, height: 1 },
+            visualCursor: [0, 10] as [number, number],
+            viewportVisualLines: [{ text: 'test query', visualRowIndex: 0 }],
+            visualScrollRow: 0,
+            lines: ['test query'],
+            cursor: [0, 10] as [number, number],
+            selectionAnchor: undefined,
+          } as unknown as TextBuffer,
+          searchQuery: 'test query',
+          setSearchQuery: vi.fn(),
+          maxLabelWidth: 10,
+        } as unknown as SearchListState<GenericListItem>;
+      },
+    );
+
+    renderView();
+
+    await waitFor(() => {
+      expect(useRegistrySearch).toHaveBeenCalledWith(
+        expect.objectContaining({
+          onSearch: mockSearch,
+        }),
+      );
+    });
+  });
+});

packages/cli/src/ui/components/views/ExtensionRegistryView.tsx

@@ -0,0 +1,200 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import type React from 'react';
+import { useMemo, useCallback } from 'react';
+import { Box, Text } from 'ink';
+import type { RegistryExtension } from '../../../config/extensionRegistryClient.js';
+
+import {
+  SearchableList,
+  type GenericListItem,
+} from '../shared/SearchableList.js';
+import { theme } from '../../semantic-colors.js';
+
+import { useExtensionRegistry } from '../../hooks/useExtensionRegistry.js';
+import { ExtensionUpdateState } from '../../state/extensions.js';
+import { useExtensionUpdates } from '../../hooks/useExtensionUpdates.js';
+import { useConfig } from '../../contexts/ConfigContext.js';
+import type { ExtensionManager } from '../../../config/extension-manager.js';
+import { useRegistrySearch } from '../../hooks/useRegistrySearch.js';
+
+interface ExtensionRegistryViewProps {
+  onSelect?: (extension: RegistryExtension) => void;
+  onClose?: () => void;
+  extensionManager: ExtensionManager;
+}
+
+interface ExtensionItem extends GenericListItem {
+  extension: RegistryExtension;
+}
+
+export function ExtensionRegistryView({
+  onSelect,
+  onClose,
+  extensionManager,
+}: ExtensionRegistryViewProps): React.JSX.Element {
+  const { extensions, loading, error, search } = useExtensionRegistry();
+  const config = useConfig();
+
+  const { extensionsUpdateState } = useExtensionUpdates(
+    extensionManager,
+    () => 0,
+    config.getEnableExtensionReloading(),
+  );
+
+  const installedExtensions = extensionManager.getExtensions();
+
+  const items: ExtensionItem[] = useMemo(
+    () =>
+      extensions.map((ext) => ({
+        key: ext.id,
+        label: ext.extensionName,
+        description: ext.extensionDescription || ext.repoDescription,
+        extension: ext,
+      })),
+    [extensions],
+  );
+
+  const handleSelect = useCallback(
+    (item: ExtensionItem) => {
+      onSelect?.(item.extension);
+    },
+    [onSelect],
+  );
+
+  const renderItem = useCallback(
+    (item: ExtensionItem, isActive: boolean, _labelWidth: number) => {
+      const isInstalled = installedExtensions.some(
+        (e) => e.name === item.extension.extensionName,
+      );
+      const updateState = extensionsUpdateState.get(
+        item.extension.extensionName,
+      );
+      const hasUpdate = updateState === ExtensionUpdateState.UPDATE_AVAILABLE;
+
+      return (
+        <Box flexDirection="row" width="100%" justifyContent="space-between">
+          <Box flexDirection="row" flexShrink={1} minWidth={0}>
+            <Box width={2} flexShrink={0}>
+              <Text
+                color={isActive ? theme.status.success : theme.text.secondary}
+              >
+                {isActive ? '> ' : '  '}
+              </Text>
+            </Box>
+            <Box flexShrink={0}>
+              <Text
+                bold={isActive}
+                color={isActive ? theme.status.success : theme.text.primary}
+              >
+                {item.label}
+              </Text>
+            </Box>
+            <Box flexShrink={0} marginX={1}>
+              <Text color={theme.text.secondary}>|</Text>
+            </Box>
+            {isInstalled && (
+              <Box marginRight={1} flexShrink={0}>
+                <Text color={theme.status.success}>[Installed]</Text>
+              </Box>
+            )}
+            {hasUpdate && (
+              <Box marginRight={1} flexShrink={0}>
+                <Text color={theme.status.warning}>[Update available]</Text>
+              </Box>
+            )}
+            <Box flexShrink={1} minWidth={0}>
+              <Text color={theme.text.secondary} wrap="truncate-end">
+                {item.description}
+              </Text>
+            </Box>
+          </Box>
+          <Box flexShrink={0} marginLeft={2} width={8} flexDirection="row">
+            <Text color={theme.status.warning}>⭐</Text>
+            <Text
+              color={isActive ? theme.status.success : theme.text.secondary}
+            >
+              {' '}
+              {item.extension.stars || 0}
+            </Text>
+          </Box>
+        </Box>
+      );
+    },
+    [installedExtensions, extensionsUpdateState],
+  );
+
+  const header = useMemo(
+    () => (
+      <Box flexDirection="row" justifyContent="space-between" width="100%">
+        <Box flexShrink={1}>
+          <Text color={theme.text.secondary} wrap="truncate">
+            Browse and search extensions from the registry.
+          </Text>
+        </Box>
+        <Box flexShrink={0} marginLeft={2}>
+          <Text color={theme.text.secondary}>
+            {installedExtensions.length &&
+              `${installedExtensions.length} installed`}
+          </Text>
+        </Box>
+      </Box>
+    ),
+    [installedExtensions.length],
+  );
+
+  const footer = useCallback(
+    ({
+      startIndex,
+      endIndex,
+      totalVisible,
+    }: {
+      startIndex: number;
+      endIndex: number;
+      totalVisible: number;
+    }) => (
+      <Text color={theme.text.secondary}>
+        ({startIndex + 1}-{endIndex}) / {totalVisible}
+      </Text>
+    ),
+    [],
+  );
+
+  if (loading) {
+    return (
+      <Box padding={1}>
+        <Text color={theme.text.secondary}>Loading extensions...</Text>
+      </Box>
+    );
+  }
+
+  if (error) {
+    return (
+      <Box padding={1} flexDirection="column">
+        <Text color={theme.status.error}>Error loading extensions:</Text>
+        <Text color={theme.text.secondary}>{error}</Text>
+      </Box>
+    );
+  }
+
+  return (
+    <SearchableList<ExtensionItem>
+      title="Extensions"
+      items={items}
+      onSelect={handleSelect}
+      onClose={onClose || (() => {})}
+      searchPlaceholder="Search extension gallery"
+      renderItem={renderItem}
+      header={header}
+      footer={footer}
+      maxItemsToShow={8}
+      useSearch={useRegistrySearch}
+      onSearch={search}
+      resetSelectionOnItemsChange={true}
+    />
+  );
+}

packages/cli/src/ui/hooks/useExtensionRegistry.ts

@@ -0,0 +1,101 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { useState, useEffect, useMemo, useCallback, useRef } from 'react';
+import {
+  ExtensionRegistryClient,
+  type RegistryExtension,
+} from '../../config/extensionRegistryClient.js';
+
+export interface UseExtensionRegistryResult {
+  extensions: RegistryExtension[];
+  loading: boolean;
+  error: string | null;
+  search: (query: string) => void;
+}
+
+export function useExtensionRegistry(
+  initialQuery = '',
+): UseExtensionRegistryResult {
+  const [extensions, setExtensions] = useState<RegistryExtension[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+
+  const client = useMemo(() => new ExtensionRegistryClient(), []);
+
+  // Ref to track the latest query to avoid race conditions
+  const latestQueryRef = useRef(initialQuery);
+
+  // Ref for debounce timeout
+  const debounceTimeoutRef = useRef<NodeJS.Timeout | undefined>(undefined);
+
+  const searchExtensions = useCallback(
+    async (query: string) => {
+      try {
+        setLoading(true);
+        const results = await client.searchExtensions(query);
+
+        // Only update if this is still the latest query
+        if (query === latestQueryRef.current) {
+          // Check if results are different from current extensions
+          setExtensions((prev) => {
+            if (
+              prev.length === results.length &&
+              prev.every((ext, i) => ext.id === results[i].id)
+            ) {
+              return prev;
+            }
+            return results;
+          });
+          setError(null);
+          setLoading(false);
+        }
+      } catch (err) {
+        if (query === latestQueryRef.current) {
+          setError(err instanceof Error ? err.message : String(err));
+          setExtensions([]);
+          setLoading(false);
+        }
+      }
+    },
+    [client],
+  );
+
+  const search = useCallback(
+    (query: string) => {
+      latestQueryRef.current = query;
+
+      // Clear existing timeout
+      if (debounceTimeoutRef.current) {
+        clearTimeout(debounceTimeoutRef.current);
+      }
+
+      // Debounce
+      debounceTimeoutRef.current = setTimeout(() => {
+        void searchExtensions(query);
+      }, 300);
+    },
+    [searchExtensions],
+  );
+
+  // Initial load
+  useEffect(() => {
+    void searchExtensions(initialQuery);
+
+    return () => {
+      if (debounceTimeoutRef.current) {
+        clearTimeout(debounceTimeoutRef.current);
+      }
+    };
+  }, [initialQuery, searchExtensions]);
+
+  return {
+    extensions,
+    loading,
+    error,
+    search,
+  };
+}

packages/cli/src/ui/hooks/useRegistrySearch.ts

@@ -0,0 +1,67 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { useState, useEffect } from 'react';
+import {
+  useTextBuffer,
+  type TextBuffer,
+} from '../components/shared/text-buffer.js';
+import { useUIState } from '../contexts/UIStateContext.js';
+import type { GenericListItem } from '../components/shared/SearchableList.js';
+
+const MIN_VIEWPORT_WIDTH = 20;
+const VIEWPORT_WIDTH_OFFSET = 8;
+
+export interface UseRegistrySearchResult<T extends GenericListItem> {
+  filteredItems: T[];
+  searchBuffer: TextBuffer | undefined;
+  searchQuery: string;
+  setSearchQuery: (query: string) => void;
+  maxLabelWidth: number;
+}
+
+export function useRegistrySearch<T extends GenericListItem>(props: {
+  items: T[];
+  initialQuery?: string;
+  onSearch?: (query: string) => void;
+}): UseRegistrySearchResult<T> {
+  const { items, initialQuery = '', onSearch } = props;
+
+  const [searchQuery, setSearchQuery] = useState(initialQuery);
+
+  useEffect(() => {
+    onSearch?.(searchQuery);
+  }, [searchQuery, onSearch]);
+
+  const { mainAreaWidth } = useUIState();
+  const viewportWidth = Math.max(
+    MIN_VIEWPORT_WIDTH,
+    mainAreaWidth - VIEWPORT_WIDTH_OFFSET,
+  );
+
+  const searchBuffer = useTextBuffer({
+    initialText: searchQuery,
+    initialCursorOffset: searchQuery.length,
+    viewport: {
+      width: viewportWidth,
+      height: 1,
+    },
+    singleLine: true,
+    onChange: (text) => setSearchQuery(text),
+  });
+
+  const maxLabelWidth = 0;
+
+  const filteredItems = items;
+
+  return {
+    filteredItems,
+    searchBuffer,
+    searchQuery,
+    setSearchQuery,
+    maxLabelWidth,
+  };
+}

packages/core/src/scheduler/policy.ts

@@ -77,7 +77,10 @@ export async function checkPolicy(
     }
   }
 
-  return { decision, rule: result.rule };
+  return {
+    decision,
+    rule: result.rule,
+  };
 }
 
 /**

packages/core/src/scheduler/tool-executor.ts

@@ -192,6 +192,8 @@ export class ToolExecutor {
       tool: call.tool,
       invocation: call.invocation,
       durationMs: startTime ? Date.now() - startTime : undefined,
+      startTime,
+      endTime: Date.now(),
       outcome: call.outcome,
     };
   }
@@ -263,6 +265,8 @@ export class ToolExecutor {
       response: successResponse,
       invocation: call.invocation,
       durationMs: startTime ? Date.now() - startTime : undefined,
+      startTime,
+      endTime: Date.now(),
       outcome: call.outcome,
     };
   }
@@ -287,6 +291,8 @@ export class ToolExecutor {
       response,
       tool: call.tool,
       durationMs: startTime ? Date.now() - startTime : undefined,
+      startTime,
+      endTime: Date.now(),
       outcome: call.outcome,
     };
   }

packages/core/src/scheduler/types.ts

@@ -86,6 +86,8 @@ export type ErroredToolCall = {
   response: ToolCallResponseInfo;
   tool?: AnyDeclarativeTool;
   durationMs?: number;
+  startTime?: number;
+  endTime?: number;
   outcome?: ToolConfirmationOutcome;
   schedulerId?: string;
   approvalMode?: ApprovalMode;
@@ -98,6 +100,8 @@ export type SuccessfulToolCall = {
   response: ToolCallResponseInfo;
   invocation: AnyToolInvocation;
   durationMs?: number;
+  startTime?: number;
+  endTime?: number;
   outcome?: ToolConfirmationOutcome;
   schedulerId?: string;
   approvalMode?: ApprovalMode;
@@ -125,6 +129,8 @@ export type CancelledToolCall = {
   tool: AnyDeclarativeTool;
   invocation: AnyToolInvocation;
   durationMs?: number;
+  startTime?: number;
+  endTime?: number;
   outcome?: ToolConfirmationOutcome;
   schedulerId?: string;
   approvalMode?: ApprovalMode;

packages/core/src/telemetry/types.ts

@@ -243,6 +243,8 @@ export class ToolCallEvent implements BaseTelemetryEvent {
   mcp_server_name?: string;
   extension_name?: string;
   extension_id?: string;
+  start_time?: number;
+  end_time?: number;
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   metadata?: { [key: string]: any };
 
@@ -256,6 +258,8 @@ export class ToolCallEvent implements BaseTelemetryEvent {
     prompt_id: string,
     tool_type: 'native' | 'mcp',
     error?: string,
+    start_time?: number,
+    end_time?: number,
   );
   constructor(
     call?: CompletedToolCall,
@@ -266,6 +270,8 @@ export class ToolCallEvent implements BaseTelemetryEvent {
     prompt_id?: string,
     tool_type?: 'native' | 'mcp',
     error?: string,
+    start_time?: number,
+    end_time?: number,
   ) {
     this['event.name'] = 'tool_call';
     this['event.timestamp'] = new Date().toISOString();
@@ -282,6 +288,8 @@ export class ToolCallEvent implements BaseTelemetryEvent {
       this.error_type = call.response.errorType;
       this.prompt_id = call.request.prompt_id;
       this.content_length = call.response.contentLength;
+      this.start_time = call.startTime;
+      this.end_time = call.endTime;
       if (
         typeof call.tool !== 'undefined' &&
         call.tool instanceof DiscoveredMCPTool
@@ -332,6 +340,8 @@ export class ToolCallEvent implements BaseTelemetryEvent {
       this.prompt_id = prompt_id!;
       this.tool_type = tool_type!;
       this.error = error;
+      this.start_time = start_time;
+      this.end_time = end_time;
     }
   }
 
@@ -351,6 +361,8 @@ export class ToolCallEvent implements BaseTelemetryEvent {
       mcp_server_name: this.mcp_server_name,
       extension_name: this.extension_name,
       extension_id: this.extension_id,
+      start_time: this.start_time,
+      end_time: this.end_time,
       metadata: this.metadata,
     };
 

packages/core/src/tools/definitions/__snapshots__/coreToolsModelSnapshots.test.ts.snap

@@ -1089,7 +1089,7 @@ exports[`coreTools snapshots for specific models > Model: gemini-3-pro-preview >
 
 exports[`coreTools snapshots for specific models > Model: gemini-3-pro-preview > snapshot for tool: grep_search_ripgrep 1`] = `
 {
-  "description": "Searches for a regular expression pattern within file contents.",
+  "description": "Searches for a regular expression pattern within file contents. This tool is FAST and optimized, powered by ripgrep. PREFERRED over standard \`run_shell_command("grep ...")\` due to better performance and automatic output limiting (defaults to 100 matches, but can be increased via \`total_max_matches\`).",
   "name": "grep_search",
   "parametersJsonSchema": {
     "properties": {

packages/core/src/tools/definitions/model-family-sets/gemini-3.ts

@@ -131,7 +131,7 @@ The user has the ability to modify \`content\`. If modified, this will be stated
   grep_search_ripgrep: {
     name: GREP_TOOL_NAME,
     description:
-      'Searches for a regular expression pattern within file contents.',
+      'Searches for a regular expression pattern within file contents. This tool is FAST and optimized, powered by ripgrep. PREFERRED over standard `run_shell_command("grep ...")` due to better performance and automatic output limiting (defaults to 100 matches, but can be increased via `total_max_matches`).',
     parametersJsonSchema: {
       type: 'object',
       properties: {

packages/core/src/tools/mcp-client.test.ts

@@ -2056,6 +2056,90 @@ describe('connectToMcpServer with OAuth', () => {
       capturedTransport._requestInit?.headers?.['Authorization'];
     expect(authHeader).toBe('Bearer test-access-token-from-discovery');
   });
+
+  it('should use discoverOAuthFromWWWAuthenticate when it succeeds and skip discoverOAuthConfig', async () => {
+    const serverUrl = 'http://test-server.com/mcp';
+    const authUrl = 'http://auth.example.com/auth';
+    const tokenUrl = 'http://auth.example.com/token';
+    const wwwAuthHeader = `Bearer realm="test", resource_metadata="http://test-server.com/.well-known/oauth-protected-resource"`;
+
+    vi.mocked(mockedClient.connect).mockRejectedValueOnce(
+      new StreamableHTTPError(
+        401,
+        `Unauthorized\nwww-authenticate: ${wwwAuthHeader}`,
+      ),
+    );
+
+    vi.mocked(OAuthUtils.discoverOAuthFromWWWAuthenticate).mockResolvedValue({
+      authorizationUrl: authUrl,
+      tokenUrl,
+      scopes: ['read'],
+    });
+
+    vi.mocked(mockedClient.connect).mockResolvedValueOnce(undefined);
+
+    const client = await connectToMcpServer(
+      '0.0.1',
+      'test-server',
+      { httpUrl: serverUrl, oauth: { enabled: true } },
+      false,
+      workspaceContext,
+      EMPTY_CONFIG,
+    );
+
+    expect(client).toBe(mockedClient);
+    expect(OAuthUtils.discoverOAuthFromWWWAuthenticate).toHaveBeenCalledWith(
+      wwwAuthHeader,
+      serverUrl,
+    );
+    expect(OAuthUtils.discoverOAuthConfig).not.toHaveBeenCalled();
+    expect(mockAuthProvider.authenticate).toHaveBeenCalledOnce();
+  });
+
+  it('should fall back to extractBaseUrl + discoverOAuthConfig when discoverOAuthFromWWWAuthenticate returns null', async () => {
+    const serverUrl = 'http://test-server.com/mcp';
+    const baseUrl = 'http://test-server.com';
+    const authUrl = 'http://auth.example.com/auth';
+    const tokenUrl = 'http://auth.example.com/token';
+    const wwwAuthHeader = `Bearer realm="test"`;
+
+    vi.mocked(mockedClient.connect).mockRejectedValueOnce(
+      new StreamableHTTPError(
+        401,
+        `Unauthorized\nwww-authenticate: ${wwwAuthHeader}`,
+      ),
+    );
+
+    vi.mocked(OAuthUtils.discoverOAuthFromWWWAuthenticate).mockResolvedValue(
+      null,
+    );
+    vi.mocked(OAuthUtils.extractBaseUrl).mockReturnValue(baseUrl);
+    vi.mocked(OAuthUtils.discoverOAuthConfig).mockResolvedValue({
+      authorizationUrl: authUrl,
+      tokenUrl,
+      scopes: ['read'],
+    });
+
+    vi.mocked(mockedClient.connect).mockResolvedValueOnce(undefined);
+
+    const client = await connectToMcpServer(
+      '0.0.1',
+      'test-server',
+      { httpUrl: serverUrl, oauth: { enabled: true } },
+      false,
+      workspaceContext,
+      EMPTY_CONFIG,
+    );
+
+    expect(client).toBe(mockedClient);
+    expect(OAuthUtils.discoverOAuthFromWWWAuthenticate).toHaveBeenCalledWith(
+      wwwAuthHeader,
+      serverUrl,
+    );
+    expect(OAuthUtils.extractBaseUrl).toHaveBeenCalledWith(serverUrl);
+    expect(OAuthUtils.discoverOAuthConfig).toHaveBeenCalledWith(baseUrl);
+    expect(mockAuthProvider.authenticate).toHaveBeenCalledOnce();
+  });
 });
 
 describe('connectToMcpServer - HTTP→SSE fallback', () => {

packages/core/src/tools/mcp-client.ts

@@ -719,18 +719,17 @@ async function handleAutomaticOAuth(
   try {
     debugLogger.log(`🔐 '${mcpServerName}' requires OAuth authentication`);
 
-    // Always try to parse the resource metadata URI from the www-authenticate header
-    let oauthConfig;
-    const resourceMetadataUri =
-      OAuthUtils.parseWWWAuthenticateHeader(wwwAuthenticate);
-    if (resourceMetadataUri) {
-      oauthConfig = await OAuthUtils.discoverOAuthConfig(resourceMetadataUri);
-    } else if (hasNetworkTransport(mcpServerConfig)) {
+    const serverUrl = mcpServerConfig.httpUrl || mcpServerConfig.url;
+
+    // Try to discover OAuth config from the WWW-Authenticate header first
+    let oauthConfig = await OAuthUtils.discoverOAuthFromWWWAuthenticate(
+      wwwAuthenticate,
+      serverUrl,
+    );
+
+    if (!oauthConfig && hasNetworkTransport(mcpServerConfig)) {
       // Fallback: try to discover OAuth config from the base URL
-      const serverUrl = new URL(
-        mcpServerConfig.httpUrl || mcpServerConfig.url!,
-      );
-      const baseUrl = `${serverUrl.protocol}//${serverUrl.host}`;
+      const baseUrl = OAuthUtils.extractBaseUrl(serverUrl!);
       oauthConfig = await OAuthUtils.discoverOAuthConfig(baseUrl);
     }
 
@@ -754,8 +753,6 @@ async function handleAutomaticOAuth(
     };
 
     // Perform OAuth authentication
-    // Pass the server URL for proper discovery
-    const serverUrl = mcpServerConfig.httpUrl || mcpServerConfig.url;
     debugLogger.log(
       `Starting OAuth authentication for server '${mcpServerName}'...`,
     );

packages/core/src/tools/web-fetch.test.ts

@@ -183,6 +183,26 @@ describe('WebFetchTool', () => {
   });
 
   describe('execute', () => {
+    it('should return WEB_FETCH_PROCESSING_ERROR on rate limit exceeded', async () => {
+      vi.spyOn(fetchUtils, 'isPrivateIp').mockReturnValue(false);
+      mockGenerateContent.mockResolvedValue({
+        candidates: [{ content: { parts: [{ text: 'response' }] } }],
+      });
+      const tool = new WebFetchTool(mockConfig, bus);
+      const params = { prompt: 'fetch https://ratelimit.example.com' };
+      const invocation = tool.build(params);
+
+      // Execute 10 times to hit the limit
+      for (let i = 0; i < 10; i++) {
+        await invocation.execute(new AbortController().signal);
+      }
+
+      // The 11th time should fail due to rate limit
+      const result = await invocation.execute(new AbortController().signal);
+      expect(result.error?.type).toBe(ToolErrorType.WEB_FETCH_PROCESSING_ERROR);
+      expect(result.error?.message).toContain('Rate limit exceeded for host');
+    });
+
     it('should return WEB_FETCH_FALLBACK_FAILED on fallback fetch failure', async () => {
       vi.spyOn(fetchUtils, 'isPrivateIp').mockReturnValue(true);
       vi.spyOn(fetchUtils, 'fetchWithTimeout').mockRejectedValue(

packages/core/src/tools/web-fetch.ts

@@ -33,10 +33,46 @@ import { debugLogger } from '../utils/debugLogger.js';
 import { retryWithBackoff } from '../utils/retry.js';
 import { WEB_FETCH_DEFINITION } from './definitions/coreTools.js';
 import { resolveToolDeclaration } from './definitions/resolver.js';
+import { LRUCache } from 'mnemonist';
 
 const URL_FETCH_TIMEOUT_MS = 10000;
 const MAX_CONTENT_LENGTH = 100000;
 
+// Rate limiting configuration
+const RATE_LIMIT_WINDOW_MS = 60000; // 1 minute
+const MAX_REQUESTS_PER_WINDOW = 10;
+const hostRequestHistory = new LRUCache<string, number[]>(1000);
+
+function checkRateLimit(url: string): {
+  allowed: boolean;
+  waitTimeMs?: number;
+} {
+  try {
+    const hostname = new URL(url).hostname;
+    const now = Date.now();
+    const windowStart = now - RATE_LIMIT_WINDOW_MS;
+
+    let history = hostRequestHistory.get(hostname) || [];
+    // Clean up old timestamps
+    history = history.filter((timestamp) => timestamp > windowStart);
+
+    if (history.length >= MAX_REQUESTS_PER_WINDOW) {
+      // Calculate wait time based on the oldest timestamp in the current window
+      const oldestTimestamp = history[0];
+      const waitTimeMs = oldestTimestamp + RATE_LIMIT_WINDOW_MS - now;
+      hostRequestHistory.set(hostname, history); // Update cleaned history
+      return { allowed: false, waitTimeMs: Math.max(0, waitTimeMs) };
+    }
+
+    history.push(now);
+    hostRequestHistory.set(hostname, history);
+    return { allowed: true };
+  } catch (_e) {
+    // If URL parsing fails, we fallback to allowed (should be caught by parsePrompt anyway)
+    return { allowed: true };
+  }
+}
+
 /**
  * Parses a prompt to extract valid URLs and identify malformed ones.
  */
@@ -258,6 +294,23 @@ ${textContent}
     const userPrompt = this.params.prompt;
     const { validUrls: urls } = parsePrompt(userPrompt);
     const url = urls[0];
+
+    // Enforce rate limiting
+    const rateLimitResult = checkRateLimit(url);
+    if (!rateLimitResult.allowed) {
+      const waitTimeSecs = Math.ceil((rateLimitResult.waitTimeMs || 0) / 1000);
+      const errorMessage = `Rate limit exceeded for host. Please wait ${waitTimeSecs} seconds before trying again.`;
+      debugLogger.warn(`[WebFetchTool] Rate limit exceeded for ${url}`);
+      return {
+        llmContent: `Error: ${errorMessage}`,
+        returnDisplay: `Error: ${errorMessage}`,
+        error: {
+          message: errorMessage,
+          type: ToolErrorType.WEB_FETCH_PROCESSING_ERROR,
+        },
+      };
+    }
+
     const isPrivate = isPrivateIp(url);
 
     if (isPrivate) {

packages/test-utils/src/test-rig.ts

@@ -208,6 +208,7 @@ export interface ParsedLog {
     stdout?: string;
     stderr?: string;
     error?: string;
+    error_type?: string;
     prompt_id?: string;
   };
   scopeMetrics?: {
@@ -1255,6 +1256,8 @@ export class TestRig {
         success: boolean;
         duration_ms: number;
         prompt_id?: string;
+        error?: string;
+        error_type?: string;
       };
     }[] = [];
 
@@ -1272,6 +1275,8 @@ export class TestRig {
             success: logData.attributes.success ?? false,
             duration_ms: logData.attributes.duration_ms ?? 0,
             prompt_id: logData.attributes.prompt_id,
+            error: logData.attributes.error,
+            error_type: logData.attributes.error_type,
           },
         });
       }