Error2 reports

Fix `KeyError`

in LangChain

✅ Solution

This error typically occurs in langchain. Check the example issues for common solutions.

Related Issues

Real GitHub issues where developers encountered this error:

Bug: langchain-anthropic file_tool callback never emits args["old_path"] but _handle_rename reads it -> KeyError on every rename7h ago

bug(core): cache implementing `__len__` makes `generate`/`agenerate` raise `KeyError`Jun 24, 2026

Timeline

First reported:Jun 24, 2026

Last reported:7h ago

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