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Custom function calls aren't working
```
2025-12-23 16:04:31.052 call_06b3fcdd7226589ea58b4056dc2 error: Error encountered in LLM call: Failed to get response from any LLM provider: {"error":{"message":"{\n  "error": {\n    "code": 400,\n    "message": "Unable to submit request because function call default_api:look_up_directory in the 3. content block is missing a thought_signature. Learn more: https://docs.cloud.google.com/vertex-ai/generative-ai/docs/thought-signatures/",/n    "status": "INVALID_ARGUMENT"\n  }\n}\n","code":400,"status":"Bad Request"}} 
```

Hello <@984804268693389383> , the issue here comes from the LLM , Gemini 3 is not stable for tool calls for now , you can try GPT 4.1 is more stable

ok, do you know when Gemini 3 will be stable?

Its coming from google so I can't really give a timeline for it.