For some reason Gemma-4 with tools is not working with me through your sdk

I keep getting errors when using:
```python
response = openrouter_client.chat.send(
                    model="google/gemma-4-31b-it",
                    messages=[{"role": "user", "content": "What is the capital of France?"}],
                    tools=tools,
                )
```

why that is ?