Update prompt and grep tool definition to limit context size (#18780)

evals/frugalSearch.eval.ts

@@ -0,0 +1,134 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, expect } from 'vitest';
+import { evalTest } from './test-helper.js';
+
+describe('Frugal Search', () => {
+  const getGrepParams = (call: any): any => {
+    let args = call.toolRequest.args;
+    if (typeof args === 'string') {
+      try {
+        args = JSON.parse(args);
+      } catch (e) {
+        // Ignore parse errors
+      }
+    }
+    return args;
+  };
+
+  evalTest('USUALLY_PASSES', {
+    name: 'should use targeted search with limit',
+    prompt: 'find me a sample usage of path.resolve() in the codebase',
+    files: {
+      'package.json': JSON.stringify({
+        name: 'test-project',
+        version: '1.0.0',
+        main: 'dist/index.js',
+        scripts: {
+          build: 'tsc',
+          test: 'vitest',
+        },
+        dependencies: {
+          typescript: '^5.0.0',
+          '@types/node': '^20.0.0',
+          vitest: '^1.0.0',
+        },
+      }),
+      'src/index.ts': `
+        import { App } from './app.ts';
+        
+        const app = new App();
+        app.start();
+      `,
+      'src/app.ts': `
+        import * as path from 'path';
+        import { UserController } from './controllers/user.ts';
+
+        export class App {
+          constructor() {
+            console.log('App initialized');
+          }
+
+          public start(): void {
+            const userController = new UserController();
+            console.log('Static path:', path.resolve(__dirname, '../public'));
+          }
+        }
+      `,
+      'src/utils.ts': `
+        import * as path from 'path';
+        import * as fs from 'fs';
+
+        export function resolvePath(p: string): string {
+          return path.resolve(process.cwd(), p);
+        }
+
+        export function ensureDir(dirPath: string): void {
+          const absolutePath = path.resolve(dirPath);
+          if (!fs.existsSync(absolutePath)) {
+            fs.mkdirSync(absolutePath, { recursive: true });
+          }
+        }
+      `,
+      'src/config.ts': `
+        import * as path from 'path';
+        
+        export const config = {
+          dbPath: path.resolve(process.cwd(), 'data/db.sqlite'),
+          logLevel: 'info',
+        };
+      `,
+      'src/controllers/user.ts': `
+        import * as path from 'path';
+        
+        export class UserController {
+          public getUsers(): any[] {
+            console.log('Loading users from:', path.resolve('data/users.json'));
+            return [{ id: 1, name: 'Alice' }];
+          }
+        }
+      `,
+      'tests/app.test.ts': `
+        import { describe, it, expect } from 'vitest';
+        import * as path from 'path';
+
+        describe('App', () => {
+          it('should resolve paths', () => {
+            const p = path.resolve('test');
+            expect(p).toBeDefined();
+          });
+        });
+      `,
+    },
+    assert: async (rig) => {
+      const toolCalls = rig.readToolLogs();
+      const grepCalls = toolCalls.filter(
+        (call) => call.toolRequest.name === 'grep_search',
+      );
+
+      expect(grepCalls.length).toBeGreaterThan(0);
+
+      const hasFrugalLimit = grepCalls.some((call) => {
+        const params = getGrepParams(call);
+        // Check for explicitly set small limit for "sample" or "example" requests
+        return (
+          params.total_max_matches !== undefined &&
+          params.total_max_matches <= 100
+        );
+      });
+
+      expect(
+        hasFrugalLimit,
+        `Expected agent to use a small total_max_matches for a sample usage request. Params used: ${JSON.stringify(
+          grepCalls.map(getGrepParams),
+          null,
+          2,
+        )}`,
+      ).toBe(true);
+    },
+  });
+});