feat(telemetry): migrate Google Auth events to event-based logging and fix token storage metric

- Add GoogleAuthStartEvent and GoogleAuthEndEvent types
- Implement logGoogleAuthStart and logGoogleAuthEnd in telemetry loggers
- Update ClearcutLogger to support Google Auth events
- Update OAuth2 logic to use the new logging functions
- Fix missing 'type' attribute in recordTokenStorageInitialization metric

docs/cli/telemetry.md

@@ -32,6 +32,7 @@ Learn how to enable and setup OpenTelemetry for Gemini CLI.
     - [Metrics](#metrics)
       - [Custom](#custom)
         - [Sessions](#sessions-1)
+        - [Authentication](#authentication)
         - [Tools](#tools-1)
         - [API](#api-1)
         - [Token usage](#token-usage)
@@ -650,6 +651,16 @@ Counts CLI sessions at startup.
 
 - `gemini_cli.session.count` (Counter, Int): Incremented once per CLI startup.
 
+##### Authentication
+
+Tracks "Login with Google" OAuth flow initiation and completion.
+
+- `gemini_cli.google_auth.start` (Counter, Int): Incremented when the "Login
+  with Google" OAuth flow begins.
+
+- `gemini_cli.google_auth.end` (Counter, Int): Incremented when the "Login with
+  Google" OAuth flow completes successfully.
+
 ##### Tools
 
 Measures tool usage and latency.

packages/core/src/code_assist/oauth2.test.ts

@@ -26,6 +26,7 @@ import {
   clearOauthClientCache,
   authEvents,
 } from './oauth2.js';
+import { logGoogleAuthStart, logGoogleAuthEnd } from '../telemetry/loggers.js';
 import { UserAccountManager } from '../utils/userAccountManager.js';
 import * as fs from 'node:fs';
 import * as path from 'node:path';
@@ -105,6 +106,11 @@ vi.mock('../mcp/token-storage/hybrid-token-storage.js', () => ({
   })),
 }));
 
+vi.mock('../telemetry/loggers.js', () => ({
+  logGoogleAuthStart: vi.fn(),
+  logGoogleAuthEnd: vi.fn(),
+}));
+
 const mockConfig = {
   getNoBrowser: () => false,
   getProxy: () => 'http://test.proxy.com:8080',
@@ -1385,6 +1391,62 @@ describe('oauth2', () => {
       });
     });
 
+    describe('onboarding telemetry', () => {
+      it('should record onboarding start and end events for LOGIN_WITH_GOOGLE', async () => {
+        const mockOAuth2Client = {
+          setCredentials: vi.fn(),
+          getAccessToken: vi.fn().mockResolvedValue({ token: 'mock-token' }),
+          getTokenInfo: vi.fn().mockResolvedValue({}),
+          on: vi.fn(),
+        } as unknown as OAuth2Client;
+        vi.mocked(OAuth2Client).mockImplementation(() => mockOAuth2Client);
+
+        const cachedCreds = { refresh_token: 'test-token' };
+        const credsPath = path.join(
+          tempHomeDir,
+          GEMINI_DIR,
+          'oauth_creds.json',
+        );
+        await fs.promises.mkdir(path.dirname(credsPath), { recursive: true });
+        await fs.promises.writeFile(credsPath, JSON.stringify(cachedCreds));
+
+        await getOauthClient(AuthType.LOGIN_WITH_GOOGLE, mockConfig);
+
+        expect(logGoogleAuthStart).toHaveBeenCalledWith(
+          mockConfig,
+          expect.any(Object),
+        );
+        expect(logGoogleAuthEnd).toHaveBeenCalledWith(
+          mockConfig,
+          expect.any(Object),
+        );
+      });
+
+      it('should NOT record google auth events for non-LOGIN_WITH_GOOGLE auth types', async () => {
+        const mockOAuth2Client = {
+          setCredentials: vi.fn(),
+          getAccessToken: vi.fn().mockResolvedValue({ token: 'mock-token' }),
+          getTokenInfo: vi.fn().mockResolvedValue({}),
+          on: vi.fn(),
+        } as unknown as OAuth2Client;
+        vi.mocked(OAuth2Client).mockImplementation(() => mockOAuth2Client);
+
+        const cachedCreds = { refresh_token: 'test-token' };
+        const credsPath = path.join(
+          tempHomeDir,
+          GEMINI_DIR,
+          'oauth_creds.json',
+        );
+        await fs.promises.mkdir(path.dirname(credsPath), { recursive: true });
+        await fs.promises.writeFile(credsPath, JSON.stringify(cachedCreds));
+
+        await getOauthClient(AuthType.COMPUTE_ADC, mockConfig);
+
+        expect(recordGoogleAuthStart).not.toHaveBeenCalled();
+        expect(recordGoogleAuthEnd).not.toHaveBeenCalled();
+      });
+    });
+
     describe('clearCachedCredentialFile', () => {
       it('should clear cached credentials and Google account', async () => {
         const cachedCreds = { refresh_token: 'test-token' };

packages/core/src/code_assist/oauth2.ts

@@ -21,6 +21,11 @@ import { EventEmitter } from 'node:events';
 import open from 'open';
 import path from 'node:path';
 import { promises as fs } from 'node:fs';
+import { logGoogleAuthStart, logGoogleAuthEnd } from '../telemetry/loggers.js';
+import {
+  GoogleAuthStartEvent,
+  GoogleAuthEndEvent,
+} from '../telemetry/types.js';
 import type { Config } from '../config/config.js';
 import {
   getErrorMessage,
@@ -113,6 +118,12 @@ async function initOauthClient(
   authType: AuthType,
   config: Config,
 ): Promise<AuthClient> {
+  const logGoogleAuthEndIfApplicable = () => {
+    if (authType === AuthType.LOGIN_WITH_GOOGLE) {
+      logGoogleAuthEnd(config, new GoogleAuthEndEvent());
+    }
+  };
+
   const credentials = await fetchCachedCredentials();
 
   if (
@@ -142,6 +153,11 @@ async function initOauthClient(
       proxy: config.getProxy(),
     },
   });
+
+  if (authType === AuthType.LOGIN_WITH_GOOGLE) {
+    logGoogleAuthStart(config, new GoogleAuthStartEvent());
+  }
+
   const useEncryptedStorage = getUseEncryptedStorageFlag();
 
   if (
@@ -152,6 +168,9 @@ async function initOauthClient(
       access_token: process.env['GOOGLE_CLOUD_ACCESS_TOKEN'],
     });
     await fetchAndCacheUserInfo(client);
+    if (authType === AuthType.LOGIN_WITH_GOOGLE) {
+      recordGoogleAuthEnd(config);
+    }
     return client;
   }
 
@@ -188,6 +207,7 @@ async function initOauthClient(
         debugLogger.log('Loaded cached credentials.');
         await triggerPostAuthCallbacks(credentials as Credentials);
 
+        logGoogleAuthEndIfApplicable();
         return client;
       }
     } catch (error) {
@@ -279,6 +299,7 @@ async function initOauthClient(
     }
 
     await triggerPostAuthCallbacks(client.credentials);
+    logGoogleAuthEndIfApplicable();
   } else {
     // In ACP mode, we skip the interactive consent and directly open the browser
     if (!config.getAcpMode()) {
@@ -385,6 +406,7 @@ async function initOauthClient(
     });
 
     await triggerPostAuthCallbacks(client.credentials);
+    logGoogleAuthEndIfApplicable();
   }
 
   return client;

packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts

@@ -50,6 +50,8 @@ import type {
   KeychainAvailabilityEvent,
   TokenStorageInitializationEvent,
   StartupStatsEvent,
+  GoogleAuthStartEvent,
+  GoogleAuthEndEvent,
 } from '../types.js';
 import { EventMetadataKey } from './event-metadata-key.js';
 import type { Config } from '../../config/config.js';
@@ -116,6 +118,8 @@ export enum EventNames {
   TOOL_OUTPUT_MASKING = 'tool_output_masking',
   KEYCHAIN_AVAILABILITY = 'keychain_availability',
   TOKEN_STORAGE_INITIALIZATION = 'token_storage_initialization',
+  GOOGLE_AUTH_START = 'google_auth_start',
+  GOOGLE_AUTH_END = 'google_auth_end',
   CONSECA_POLICY_GENERATION = 'conseca_policy_generation',
   CONSECA_VERDICT = 'conseca_verdict',
   STARTUP_STATS = 'startup_stats',
@@ -1693,6 +1697,16 @@ export class ClearcutLogger {
     this.flushIfNeeded();
   }
 
+  logGoogleAuthStartEvent(_event: GoogleAuthStartEvent): void {
+    this.enqueueLogEvent(this.createLogEvent(EventNames.GOOGLE_AUTH_START, []));
+    this.flushIfNeeded();
+  }
+
+  logGoogleAuthEndEvent(_event: GoogleAuthEndEvent): void {
+    this.enqueueLogEvent(this.createLogEvent(EventNames.GOOGLE_AUTH_END, []));
+    this.flushIfNeeded();
+  }
+
   logStartupStatsEvent(event: StartupStatsEvent): void {
     const data: EventValue[] = [
       {

packages/core/src/telemetry/loggers.ts

@@ -56,6 +56,8 @@ import {
   type ToolOutputMaskingEvent,
   type KeychainAvailabilityEvent,
   type TokenStorageInitializationEvent,
+  type GoogleAuthStartEvent,
+  type GoogleAuthEndEvent,
 } from './types.js';
 import {
   recordApiErrorMetrics,
@@ -77,6 +79,8 @@ import {
   recordKeychainAvailability,
   recordTokenStorageInitialization,
   recordInvalidChunk,
+  recordGoogleAuthStart,
+  recordGoogleAuthEnd,
 } from './metrics.js';
 import { bufferTelemetryEvent } from './sdk.js';
 import { uiTelemetryService, type UiEvent } from './uiTelemetry.js';
@@ -844,6 +848,40 @@ export function logTokenStorageInitialization(
   });
 }
 
+export function logGoogleAuthStart(
+  config: Config,
+  event: GoogleAuthStartEvent,
+): void {
+  ClearcutLogger.getInstance(config)?.logGoogleAuthStartEvent(event);
+  bufferTelemetryEvent(() => {
+    const logger = logs.getLogger(SERVICE_NAME);
+    const logRecord: LogRecord = {
+      body: event.toLogBody(),
+      attributes: event.toOpenTelemetryAttributes(config),
+    };
+    logger.emit(logRecord);
+
+    recordGoogleAuthStart(config);
+  });
+}
+
+export function logGoogleAuthEnd(
+  config: Config,
+  event: GoogleAuthEndEvent,
+): void {
+  ClearcutLogger.getInstance(config)?.logGoogleAuthEndEvent(event);
+  bufferTelemetryEvent(() => {
+    const logger = logs.getLogger(SERVICE_NAME);
+    const logRecord: LogRecord = {
+      body: event.toLogBody(),
+      attributes: event.toOpenTelemetryAttributes(config),
+    };
+    logger.emit(logRecord);
+
+    recordGoogleAuthEnd(config);
+  });
+}
+
 export function logBillingEvent(
   config: Config,
   event: BillingTelemetryEvent,

packages/core/src/telemetry/metrics.ts

@@ -50,6 +50,8 @@ const KEYCHAIN_AVAILABILITY_COUNT = 'gemini_cli.keychain.availability.count';
 const TOKEN_STORAGE_TYPE_COUNT = 'gemini_cli.token_storage.type.count';
 const OVERAGE_OPTION_COUNT = 'gemini_cli.overage_option.count';
 const CREDIT_PURCHASE_COUNT = 'gemini_cli.credit_purchase.count';
+const EVENT_GOOGLE_AUTH_START = 'gemini_cli.google_auth.start';
+const EVENT_GOOGLE_AUTH_END = 'gemini_cli.google_auth.end';
 
 // Agent Metrics
 const AGENT_RUN_COUNT = 'gemini_cli.agent.run.count';
@@ -288,6 +290,18 @@ const COUNTER_DEFINITIONS = {
       model: string;
     },
   },
+  [EVENT_GOOGLE_AUTH_START]: {
+    description: 'Counts auth "Login with Google" started.',
+    valueType: ValueType.INT,
+    assign: (c: Counter) => (googleAuthStartCounter = c),
+    attributes: {} as Record<string, never>,
+  },
+  [EVENT_GOOGLE_AUTH_END]: {
+    description: 'Counts auth "Login with Google" succeeded.',
+    valueType: ValueType.INT,
+    assign: (c: Counter) => (googleAuthEndCounter = c),
+    attributes: {} as Record<string, never>,
+  },
 } as const;
 
 const HISTOGRAM_DEFINITIONS = {
@@ -536,7 +550,7 @@ const PERFORMANCE_HISTOGRAM_DEFINITIONS = {
   },
 } as const;
 
-type AllMetricDefs = typeof COUNTER_DEFINITIONS &
+export type AllMetricDefs = typeof COUNTER_DEFINITIONS &
   typeof HISTOGRAM_DEFINITIONS &
   typeof PERFORMANCE_COUNTER_DEFINITIONS &
   typeof PERFORMANCE_HISTOGRAM_DEFINITIONS;
@@ -628,6 +642,8 @@ let keychainAvailabilityCounter: Counter | undefined;
 let tokenStorageTypeCounter: Counter | undefined;
 let overageOptionCounter: Counter | undefined;
 let creditPurchaseCounter: Counter | undefined;
+let googleAuthStartCounter: Counter | undefined;
+let googleAuthEndCounter: Counter | undefined;
 
 // OpenTelemetry GenAI Semantic Convention Metrics
 let genAiClientTokenUsageHistogram: Histogram | undefined;
@@ -800,6 +816,25 @@ export function recordLinesChanged(
 
 // --- New Metric Recording Functions ---
 
+/**
+ * Records a metric for when the Google auth process starts.
+ */
+export function recordGoogleAuthStart(config: Config): void {
+  if (!googleAuthStartCounter || !isMetricsInitialized) return;
+  googleAuthStartCounter.add(
+    1,
+    baseMetricDefinition.getCommonAttributes(config),
+  );
+}
+
+/**
+ * Records a metric for when the Google auth process ends successfully.
+ */
+export function recordGoogleAuthEnd(config: Config): void {
+  if (!googleAuthEndCounter || !isMetricsInitialized) return;
+  googleAuthEndCounter.add(1, baseMetricDefinition.getCommonAttributes(config));
+}
+
 /**
  * Records a metric for when a UI frame flickers.
  */
@@ -1363,6 +1398,7 @@ export function recordTokenStorageInitialization(
     ...baseMetricDefinition.getCommonAttributes(config),
     type: event.type,
     forced: event.forced,
+    type: event.type,
   });
 }
 

packages/core/src/telemetry/types.ts

@@ -2307,6 +2307,52 @@ export class KeychainAvailabilityEvent implements BaseTelemetryEvent {
   }
 }
 
+export const EVENT_GOOGLE_AUTH_START = 'gemini_cli.google_auth.start';
+export class GoogleAuthStartEvent implements BaseTelemetryEvent {
+  'event.name': 'google_auth_start';
+  'event.timestamp': string;
+
+  constructor() {
+    this['event.name'] = 'google_auth_start';
+    this['event.timestamp'] = new Date().toISOString();
+  }
+
+  toOpenTelemetryAttributes(config: Config): LogAttributes {
+    return {
+      ...getCommonAttributes(config),
+      'event.name': EVENT_GOOGLE_AUTH_START,
+      'event.timestamp': this['event.timestamp'],
+    };
+  }
+
+  toLogBody(): string {
+    return 'Google auth started.';
+  }
+}
+
+export const EVENT_GOOGLE_AUTH_END = 'gemini_cli.google_auth.end';
+export class GoogleAuthEndEvent implements BaseTelemetryEvent {
+  'event.name': 'google_auth_end';
+  'event.timestamp': string;
+
+  constructor() {
+    this['event.name'] = 'google_auth_end';
+    this['event.timestamp'] = new Date().toISOString();
+  }
+
+  toOpenTelemetryAttributes(config: Config): LogAttributes {
+    return {
+      ...getCommonAttributes(config),
+      'event.name': EVENT_GOOGLE_AUTH_END,
+      'event.timestamp': this['event.timestamp'],
+    };
+  }
+
+  toLogBody(): string {
+    return 'Google auth succeeded.';
+  }
+}
+
 export const EVENT_TOKEN_STORAGE_INITIALIZATION =
   'gemini_cli.token_storage.initialization';
 export class TokenStorageInitializationEvent implements BaseTelemetryEvent {