Add usage limit remaining in /stats (#13843)

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

@@ -380,4 +380,38 @@ describe('CodeAssistServer', () => {
     });
     expect(response).toEqual(mockResponse);
   });
+
+  it('should call the retrieveUserQuota endpoint', async () => {
+    const client = new OAuth2Client();
+    const server = new CodeAssistServer(
+      client,
+      'test-project',
+      {},
+      'test-session',
+      UserTierId.FREE,
+    );
+    const mockResponse = {
+      buckets: [
+        {
+          modelId: 'gemini-2.5-pro',
+          tokenType: 'REQUESTS',
+          remainingFraction: 0.75,
+          resetTime: '2025-10-22T16:01:15Z',
+        },
+      ],
+    };
+    const requestPostSpy = vi
+      .spyOn(server, 'requestPost')
+      .mockResolvedValue(mockResponse);
+
+    const req = {
+      project: 'projects/my-cloudcode-project',
+      userAgent: 'CloudCodePlugin/1.0 (gaghosh)',
+    };
+
+    const response = await server.retrieveUserQuota(req);
+
+    expect(requestPostSpy).toHaveBeenCalledWith('retrieveUserQuota', req);
+    expect(response).toEqual(mockResponse);
+  });
 });

packages/core/src/code_assist/server.ts

@@ -14,6 +14,8 @@ import type {
   OnboardUserRequest,
   SetCodeAssistGlobalUserSettingRequest,
   ClientMetadata,
+  RetrieveUserQuotaRequest,
+  RetrieveUserQuotaResponse,
 } from './types.js';
 import type {
   ListExperimentsRequest,
@@ -171,6 +173,15 @@ export class CodeAssistServer implements ContentGenerator {
     );
   }
 
+  async retrieveUserQuota(
+    req: RetrieveUserQuotaRequest,
+  ): Promise<RetrieveUserQuotaResponse> {
+    return await this.requestPost<RetrieveUserQuotaResponse>(
+      'retrieveUserQuota',
+      req,
+    );
+  }
+
   async requestPost<T>(
     method: string,
     req: object,

packages/core/src/code_assist/types.ts

@@ -200,3 +200,20 @@ export interface GoogleRpcResponse {
 interface GoogleRpcErrorInfo {
   reason?: string;
 }
+
+export interface RetrieveUserQuotaRequest {
+  project: string;
+  userAgent?: string;
+}
+
+export interface BucketInfo {
+  remainingAmount?: string;
+  remainingFraction?: number;
+  resetTime?: string;
+  tokenType?: string;
+  modelId?: string;
+}
+
+export interface RetrieveUserQuotaResponse {
+  buckets?: BucketInfo[];
+}