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Overview Graphs Functional API Pregel Checkpointing Storage Caching Types Runtime Config Errors Constants Channels Agents

LangGraph Checkpoint

Checkpoint Postgres

Checkpoint SQLite

LangGraph Prebuilt

LangGraph Supervisor

LangGraph Swarm

Language

Theme

Pythonlanggraphstreamstream_channelStreamChannelfail

Method●Since v1.1

fail

Copy

fail(
    self,
    err: BaseException,
) -> None

View source on GitHub

Parameters

Name	Type	Description
`err`*	`BaseException`	The exception to surface to the subscriber.

Mark the channel as errored.