Change8
Error15 reports

Fix BadRequestError

in LangChain

Solution

BadRequestError in Langchain often arises from malformed API requests to LLMs, commonly due to incorrect input formatting or exceeding token limits. Resolve this by validating your prompt structure, reducing prompt size, and ensuring your tool outputs conform to the schema expected by the LLM, particularly when using structured output or optional parameters. Retry with adjusted parameters after verifying these aspects.

Timeline

First reported:Oct 26, 2025
Last reported:Jan 8, 2026

Need More Help?

View the full changelog and migration guides for LangChain

View LangChain Changelog