# Description This PR fixes a bug in _recursive_set_additional_properties_false used in function_calling.convert_to_openai_function. Previously, schemas with "additionalProperties=True" were not correctly overridden when strict validation was expected, which could lead to invalid OpenAI function schemas. The updated implementation ensures that: - Any schema with "additionalProperties" already set will now be forced to False under strict mode. - Recursive traversal of properties, items, and anyOf is preserved. - Function signature remains unchanged for backward compatibility. # Issue When using tool calling in OpenAI structured output strict mode (strict=True), 400: "Invalid schema for response_format XXXXX 'additionalProperties' is required to be supplied and to be false" error raises for the parameter that contains dict type. OpenAI requires additionalProperties to be set to False. Some PRs try to resolved the issue. - PR #25169 introduced _recursive_set_additional_properties_false to recursively set additionalProperties=False. - PR #26287 fixed handling of empty parameter tools for OpenAI function generation. - PR #30971 added support for Union type arguments in strict mode of OpenAI function calling / structured output. Despite these improvements, since Pydantic 2.11, it will always add `additionalProperties: True` for arbitrary dictionary schemas dict or Any (https://pydantic.dev/articles/pydantic-v2-11-release#changes). Schemas that already had additionalProperties=True in such cases were not being overridden, which this PR addresses to ensure strict mode behaves correctly in all cases. # Dependencies No Changes --------- Co-authored-by: Zhong, Yu <yzhong@freewheel.com>
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Looking for the JS/TS library? Check out LangChain.js.
LangChain is a framework for building LLM-powered applications. It helps you chain together interoperable components and third-party integrations to simplify AI application development — all while future-proofing decisions as the underlying technology evolves.
pip install -U langchain
To learn more about LangChain, check out the docs. If you’re looking for more advanced customization or agent orchestration, check out LangGraph, our framework for building controllable agent workflows.
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