add(OTel): Add OTel logging for MalformedJsonEvent (#6912)

Co-authored-by: Shnatu <snatu@google.com>
Co-authored-by: cornmander <shikhman@google.com>

docs/telemetry.md

@@ -220,6 +220,10 @@ Logs are timestamped records of specific events. The following events are logged
     - `response_text` (if applicable)
     - `auth_type`
 
+- `gemini_cli.malformed_json_response`: This event occurs when a `generateJson` response from Gemini API cannot be parsed as a json.
+  - **Attributes**:
+    - `model`
+
 - `gemini_cli.flash_fallback`: This event occurs when Gemini CLI switches to flash as fallback.
   - **Attributes**:
     - `auth_type`

packages/core/src/core/client.ts

@@ -46,13 +46,13 @@ import { ideContext } from '../ide/ideContext.js';
 import {
   logChatCompression,
   logNextSpeakerCheck,
+  logMalformedJsonResponse,
 } from '../telemetry/loggers.js';
 import {
   makeChatCompressionEvent,
   MalformedJsonResponseEvent,
   NextSpeakerCheckEvent,
 } from '../telemetry/types.js';
-import { ClearcutLogger } from '../telemetry/clearcut-logger/clearcut-logger.js';
 import { IdeContext, File } from '../ide/ideContext.js';
 
 function isThinkingSupported(model: string) {
@@ -617,7 +617,8 @@ export class GeminiClient {
       const prefix = '```json';
       const suffix = '```';
       if (text.startsWith(prefix) && text.endsWith(suffix)) {
-        ClearcutLogger.getInstance(this.config)?.logMalformedJsonResponseEvent(
+        logMalformedJsonResponse(
+          this.config,
           new MalformedJsonResponseEvent(modelToUse),
         );
         text = text

packages/core/src/telemetry/constants.ts

@@ -17,6 +17,8 @@ export const EVENT_NEXT_SPEAKER_CHECK = 'gemini_cli.next_speaker_check';
 export const EVENT_SLASH_COMMAND = 'gemini_cli.slash_command';
 export const EVENT_IDE_CONNECTION = 'gemini_cli.ide_connection';
 export const EVENT_CHAT_COMPRESSION = 'gemini_cli.chat_compression';
+export const EVENT_MALFORMED_JSON_RESPONSE =
+  'gemini_cli.malformed_json_response';
 export const METRIC_TOOL_CALL_COUNT = 'gemini_cli.tool.call.count';
 export const METRIC_TOOL_CALL_LATENCY = 'gemini_cli.tool.call.latency';
 export const METRIC_API_REQUEST_COUNT = 'gemini_cli.api.request.count';

packages/core/src/telemetry/loggers.test.ts

@@ -26,6 +26,7 @@ import {
   EVENT_TOOL_CALL,
   EVENT_USER_PROMPT,
   EVENT_FLASH_FALLBACK,
+  EVENT_MALFORMED_JSON_RESPONSE,
 } from './constants.js';
 import {
   logApiRequest,
@@ -35,6 +36,7 @@ import {
   logToolCall,
   logFlashFallback,
   logChatCompression,
+  logMalformedJsonResponse,
 } from './loggers.js';
 import { ToolCallDecision } from './tool-call-decision.js';
 import {
@@ -44,6 +46,7 @@ import {
   ToolCallEvent,
   UserPromptEvent,
   FlashFallbackEvent,
+  MalformedJsonResponseEvent,
   makeChatCompressionEvent,
 } from './types.js';
 import * as metrics from './metrics.js';
@@ -818,4 +821,31 @@ describe('loggers', () => {
       });
     });
   });
+
+  describe('logMalformedJsonResponse', () => {
+    beforeEach(() => {
+      vi.spyOn(ClearcutLogger.prototype, 'logMalformedJsonResponseEvent');
+    });
+
+    it('logs the event to Clearcut and OTEL', () => {
+      const mockConfig = makeFakeConfig();
+      const event = new MalformedJsonResponseEvent('test-model');
+
+      logMalformedJsonResponse(mockConfig, event);
+
+      expect(
+        ClearcutLogger.prototype.logMalformedJsonResponseEvent,
+      ).toHaveBeenCalledWith(event);
+
+      expect(mockLogger.emit).toHaveBeenCalledWith({
+        body: 'Malformed JSON response from test-model.',
+        attributes: {
+          'session.id': 'test-session-id',
+          'event.name': EVENT_MALFORMED_JSON_RESPONSE,
+          'event.timestamp': '2025-01-01T00:00:00.000Z',
+          model: 'test-model',
+        },
+      });
+    });
+  });
 });

packages/core/src/telemetry/loggers.ts

@@ -20,6 +20,7 @@ import {
   SERVICE_NAME,
   EVENT_SLASH_COMMAND,
   EVENT_CHAT_COMPRESSION,
+  EVENT_MALFORMED_JSON_RESPONSE,
 } from './constants.js';
 import {
   ApiErrorEvent,
@@ -36,6 +37,7 @@ import {
   SlashCommandEvent,
   KittySequenceOverflowEvent,
   ChatCompressionEvent,
+  MalformedJsonResponseEvent,
 } from './types.js';
 import {
   recordApiErrorMetrics,
@@ -449,3 +451,24 @@ export function logKittySequenceOverflow(
   };
   logger.emit(logRecord);
 }
+
+export function logMalformedJsonResponse(
+  config: Config,
+  event: MalformedJsonResponseEvent,
+): void {
+  ClearcutLogger.getInstance(config)?.logMalformedJsonResponseEvent(event);
+  if (!isTelemetrySdkInitialized()) return;
+
+  const attributes: LogAttributes = {
+    ...getCommonAttributes(config),
+    ...event,
+    'event.name': EVENT_MALFORMED_JSON_RESPONSE,
+  };
+
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: `Malformed JSON response from ${event.model}.`,
+    attributes,
+  };
+  logger.emit(logRecord);
+}