LangChain fails to return valid structured output
2 posts from 2 people2d activeSteady, +1 this weekunverified
Posts per day
The posts behind it
fix(langchain): match `handle_errors` types against the wrapped parsing error
### Submission checklist - [x] This is a bug, not a usage question. - [x] I added a clear and descriptive title that summarizes this issue. - [x] I used the GitHub search to find a similar question and didn't find it. - [x] I am sure that this is a bug in LangChain rather than...
`InjectedToolCallId` is never injected when `args_schema` is a JSON schema dict (`TypeError: missing 1 required positional argument`)
...(and that raises the "tool must always be invoked with a full model ToolCall" error when no id is available). `_injected_args_keys` does detect the parameter for this tool (`frozenset({'tool_call_id'})`); it is just never acted on for dict schemas. Expected:...
Companies and products named
About this problem
Evidence
2 posts from 2 people in 1 place, about 1 a week over 9 days. Mostly on langchain-ai/langchain. Tools named alongside: GitHub, Anthropic, OpenAI, Perplexity.
Frustration Frustration 0 of 3· Seen on GitHub issues
How it was grouped
Posts that state a pain and match the "structured-output" rule about LangChain. First post Oct 27, 2026, latest Nov 4, 2026. Unverified: fewer than 3 posts, or one person or place only. Method
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History