Add the Gemini 3 pro's thoughtSignatures support in langchain-openai #34056
Description
Checked other resources
- This is a feature request, not a bug report or usage question.
- I added a clear and descriptive title that summarizes the feature request.
- I used the GitHub search to find a similar feature request and didn't find it.
- I checked the LangChain documentation and API reference to see if this feature already exists.
- This is not related to the langchain-community package.
Package (Required)
- langchain
- langchain-openai
- langchain-anthropic
- langchain-classic
- langchain-core
- langchain-cli
- langchain-model-profiles
- langchain-tests
- langchain-text-splitters
- langchain-chroma
- langchain-deepseek
- langchain-exa
- langchain-fireworks
- langchain-groq
- langchain-huggingface
- langchain-mistralai
- langchain-nomic
- langchain-ollama
- langchain-perplexity
- langchain-prompty
- langchain-qdrant
- langchain-xai
- Other / not sure / general
Feature Description
We are currently calling Gemini 3 pro through the chain langchain-openai → OpenRouter → Gemini 3 pro.
The newly released Gemini 3 Pro requires passing back the thoughtSignatures parameter during tool calls, but this parameter is only supported in langchain-google-genai, not in langchain-openai.
Use Case
Once we add the support for thought-signatures, we can use the chain langchain-openai → OpenRouter → Gemini 3 pro.
Proposed Solution
No response
Alternatives Considered
No response
Additional Context
No response