Worked on the langchain-ai/langsmith-sdk repository to stabilize data serialization workflows in response to Pydantic V2 changes. Addressed a bug where deprecation warnings appeared when serializing non-JSON-serializable fields by introducing a model_dump(exclude_none=True) fallback, which preserves backward compatibility with Pydantic V1 and dataclasses-json. This approach improved error handling and reduced warning noise in the serialization chain, ensuring a smoother developer experience across versions. The solution was validated through unit tests and local integration checks, focusing on reliability and maintainability. Utilized Python, Pydantic, and backend development skills to enhance the robustness of client data contracts without introducing breaking changes.