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LangGraph · Type Alias

StreamWriter

StreamWriter is a callable for sending one value to LangGraph's output stream. LangGraph injects it into a node when requested as a keyword argument.

Last updated

Since
v1.2

Syntax

StreamWriter = Callable[[Any], None]

In-depth API docs are only for subscribers: parameters, examples, common mistakes and interview practice.

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  • stream_mode="custom"
  • entrypoint
  • writer
  • functional API

Source: StreamWriter | langgraph | LangChain Reference. Checked 2026-11-03.