Update OpenAI model configuration to use the new Responses API

According to OpenAI docs, the Responses API is recommended for all new projects.

https://developers.openai.com/api/docs/guides/migrate-to-responses

Author: vinzee

.changeset/sharp-eggs-appear.md

@@ -0,0 +1,5 @@
+---
+'@hyperdx/api': patch
+---
+
+Update OpenAI model configuration to use the new Responses API

packages/api/src/controllers/__tests__/ai.test.ts

@@ -13,9 +13,9 @@ const mockCreateAnthropic = jest.fn(
   (_opts?: Record<string, unknown>) => mockAnthropicFactory,
 );
 
-const mockOpenAIChatFactory = jest.fn((_model?: string) => mockOpenAIModel);
+const mockOpenAIResponsesFactory = jest.fn((_model?: string) => mockOpenAIModel);
 const mockCreateOpenAI = jest.fn((_opts?: Record<string, unknown>) => ({
-  chat: mockOpenAIChatFactory,
+  responses: mockOpenAIResponsesFactory,
 }));
 
 jest.mock('@ai-sdk/anthropic', () => ({
@@ -191,7 +191,7 @@ describe('openai provider', () => {
     expect(mockCreateOpenAI).toHaveBeenCalledWith(
       expect.objectContaining({ apiKey: 'sk-test' }),
     );
-    expect(mockOpenAIChatFactory).toHaveBeenCalledWith('gpt-4o');
+    expect(mockOpenAIResponsesFactory).toHaveBeenCalledWith('gpt-4o');
   });
 
   it('passes baseURL when AI_BASE_URL is set', () => {

packages/api/src/controllers/ai.ts

@@ -368,9 +368,7 @@ function getAnthropicModel(): LanguageModel {
 }
 
 /**
- * Configure OpenAI-compatible model.
- * Works with any OpenAI Chat Completions-compatible endpoint
- * (e.g. Azure OpenAI, OpenRouter, LiteLLM proxies).
+ * Configure OpenAI-compatible model using the Responses API (/v1/responses).
  */
 function getOpenAIModel(): LanguageModel {
   const apiKey = config.AI_API_KEY;
@@ -399,5 +397,5 @@ function getOpenAIModel(): LanguageModel {
     ...(Object.keys(headers).length > 0 && { headers }),
   });
 
-  return openai.chat(config.AI_MODEL_NAME);
+  return openai.responses(config.AI_MODEL_NAME);
 }