fix: mock OpenAI API calls at a lower level

Co-Authored-By: Han Xiao <[email protected]>

src/tools/__tests__/evaluator.test.ts

@@ -67,7 +67,19 @@ jest.mock('@ai-sdk/google', () => ({
 }));
 
 jest.mock('@ai-sdk/openai', () => ({
-  OpenAIChatLanguageModel: jest.fn()
+  OpenAIChatLanguageModel: jest.fn().mockImplementation(() => ({
+    doGenerate: jest.fn().mockResolvedValue({
+      object: mockEvalResponse,
+      usage: { totalTokens: 0, promptTokens: 0, completionTokens: 0 },
+      finishReason: 'stop',
+      warnings: [],
+      request: {},
+      response: {},
+      cached: false,
+      created: Date.now(),
+      model: 'test-model'
+    })
+  }))
 }));
 
 jest.mock('../../utils/token-tracker');