Log prompt id when a loop is detected (#4765)

Co-authored-by: N. Taylor Mullen <ntaylormullen@google.com>

packages/core/src/core/client.ts

@@ -293,7 +293,7 @@ export class GeminiClient {
     originalModel?: string,
   ): AsyncGenerator<ServerGeminiStreamEvent, Turn> {
     if (this.lastPromptId !== prompt_id) {
-      this.loopDetector.reset();
+      this.loopDetector.reset(prompt_id);
       this.lastPromptId = prompt_id;
     }
     this.sessionTurnCount++;

packages/core/src/services/loopDetectionService.test.ts

@@ -168,21 +168,21 @@ describe('LoopDetectionService', () => {
         );
       }
 
-      service.reset();
+      service.reset('');
       for (let i = 0; i < CONTENT_LOOP_THRESHOLD + 2; i++) {
         expect(service.addAndCheck(createContentEvent('obj.method()'))).toBe(
           false,
         );
       }
 
-      service.reset();
+      service.reset('');
       for (let i = 0; i < CONTENT_LOOP_THRESHOLD + 2; i++) {
         expect(
           service.addAndCheck(createContentEvent('arr.filter().map()')),
         ).toBe(false);
       }
 
-      service.reset();
+      service.reset('');
       for (let i = 0; i < CONTENT_LOOP_THRESHOLD + 2; i++) {
         expect(
           service.addAndCheck(
@@ -203,7 +203,7 @@ describe('LoopDetectionService', () => {
         service.addAndCheck(createContentEvent('This is a sentence.')),
       ).toBe(true);
 
-      service.reset();
+      service.reset('');
       for (let i = 0; i < CONTENT_LOOP_THRESHOLD - 1; i++) {
         expect(
           service.addAndCheck(createContentEvent('Is this a question? ')),
@@ -213,7 +213,7 @@ describe('LoopDetectionService', () => {
         service.addAndCheck(createContentEvent('Is this a question? ')),
       ).toBe(true);
 
-      service.reset();
+      service.reset('');
       for (let i = 0; i < CONTENT_LOOP_THRESHOLD - 1; i++) {
         expect(
           service.addAndCheck(createContentEvent('What excitement!\n')),

packages/core/src/services/loopDetectionService.ts

@@ -50,6 +50,7 @@ const SENTENCE_ENDING_PUNCTUATION_REGEX = /[.!?]+(?=\s|$)/;
  */
 export class LoopDetectionService {
   private readonly config: Config;
+  private promptId = '';
 
   // Tool call tracking
   private lastToolCallKey: string | null = null;
@@ -129,7 +130,10 @@ export class LoopDetectionService {
     if (this.toolCallRepetitionCount >= TOOL_CALL_LOOP_THRESHOLD) {
       logLoopDetected(
         this.config,
-        new LoopDetectedEvent(LoopType.CONSECUTIVE_IDENTICAL_TOOL_CALLS),
+        new LoopDetectedEvent(
+          LoopType.CONSECUTIVE_IDENTICAL_TOOL_CALLS,
+          this.promptId,
+        ),
       );
       return true;
     }
@@ -170,7 +174,10 @@ export class LoopDetectionService {
       if (this.sentenceRepetitionCount >= CONTENT_LOOP_THRESHOLD) {
         logLoopDetected(
           this.config,
-          new LoopDetectedEvent(LoopType.CHANTING_IDENTICAL_SENTENCES),
+          new LoopDetectedEvent(
+            LoopType.CHANTING_IDENTICAL_SENTENCES,
+            this.promptId,
+          ),
         );
         return true;
       }
@@ -234,7 +241,7 @@ Please analyze the conversation history to determine the possibility that the co
         }
         logLoopDetected(
           this.config,
-          new LoopDetectedEvent(LoopType.LLM_DETECTED_LOOP),
+          new LoopDetectedEvent(LoopType.LLM_DETECTED_LOOP, this.promptId),
         );
         return true;
       } else {
@@ -251,7 +258,8 @@ Please analyze the conversation history to determine the possibility that the co
   /**
    * Resets all loop detection state.
    */
-  reset(): void {
+  reset(promptId: string): void {
+    this.promptId = promptId;
     this.resetToolCallCount();
     this.resetSentenceCount();
     this.resetLlmCheckTracking();

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

@@ -481,8 +481,8 @@ export class ClearcutLogger {
   logLoopDetectedEvent(event: LoopDetectedEvent): void {
     const data = [
       {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SESSION_ID,
-        value: this.config?.getSessionId() ?? '',
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
+        value: JSON.stringify(event.prompt_id),
       },
       {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_LOOP_DETECTED_TYPE,

packages/core/src/telemetry/types.ts

@@ -256,11 +256,13 @@ export class LoopDetectedEvent {
   'event.name': 'loop_detected';
   'event.timestamp': string; // ISO 8601
   loop_type: LoopType;
+  prompt_id: string;
 
-  constructor(loop_type: LoopType) {
+  constructor(loop_type: LoopType, prompt_id: string) {
     this['event.name'] = 'loop_detected';
     this['event.timestamp'] = new Date().toISOString();
     this.loop_type = loop_type;
+    this.prompt_id = prompt_id;
   }
 }