Why is using a response_schema not supported when using grounded search?

Gemini API
,
1

This seems to a be really “Modified by moderator” limitation, especially with the regressions in the latest stable release of 2.5, which is far from stable. I really dont want to switch back to OpenAI.

response = client.models.generate_content(
            model=model,
            contents=user_prompt,
            config=GenerateContentConfig(tools=[google_search_tool],
                                         system_instruction=system_prompt,
                                         response_schema=response_schema,
                                         response_mime_type="application/json",
                                         temperature=0.6,
                                         seed=seed,
                                         thinking_config=ThinkingConfig(include_thoughts=True)))

google.genai.errors.ClientError: 400 INVALID_ARGUMENT. {‘error’: {‘code’: 400, ‘message’: “Tool use with a response mime type: ‘application/json’ is unsupported”, ‘status’: ‘INVALID_ARGUMENT’}}

Is there any plans to support this soon?

Thanks

2

UPDATE:

So it seams if you remove the response_mime_type="application/json", it at least works, and does give me back JSON. Now running it at scale to see how often if doesnt. Wish me luck.

New code:

        response = client.models.generate_content(
            model=model,
            contents=user_prompt,
            config=GenerateContentConfig(tools=[google_search_tool],
                                         system_instruction=system_prompt,
                                         response_schema=response_schema,
                                         temperature=0.6,
                                         seed=seed,
                                         thinking_config=ThinkingConfig(include_thoughts=True)))