LangChain Reference home pageLangChain ReferenceLangChain Reference
  • GitHub
  • Main Docs
Deep Agents
LangChain
LangGraph
Integrations
LangSmith
LangGraph
  • Web
  • Channels
  • Pregel
  • Prebuilt
  • Remote
  • Stream
LangGraph SDK
  • Ui
  • Client
  • Auth
  • React
  • Logging
  • React Ui
  • Utils
  • Server
  • Stream
LangGraph Checkpoint
LangGraph Checkpoint MongoDB
LangGraph Checkpoint Postgres
  • Store
LangGraph Checkpoint Redis
  • Shallow
  • Store
LangGraph Checkpoint SQLite
LangGraph Checkpoint Validation
  • Cli
LangGraph API
LangGraph CLI
LangGraph CUA
  • Utils
LangGraph Supervisor
LangGraph Swarm
⌘I

LangChain Assistant

Ask a question to get started

Enter to send•Shift+Enter new line

Menu

LangGraph
WebChannelsPregelPrebuiltRemoteStream
LangGraph SDK
UiClientAuthReactLoggingReact UiUtilsServerStream
LangGraph Checkpoint
LangGraph Checkpoint MongoDB
LangGraph Checkpoint Postgres
Store
LangGraph Checkpoint Redis
ShallowStore
LangGraph Checkpoint SQLite
LangGraph Checkpoint Validation
Cli
LangGraph API
LangGraph CLI
LangGraph CUA
Utils
LangGraph Supervisor
LangGraph Swarm
Language
Theme
JavaScript@langchain/langgraph-sdkstreamChannelEffectOptions
Interface●Since v1.9

ChannelEffectOptions

Copy
interface ChannelEffectOptions

Bases

ChannelProjectionOptions

Properties

Inherited fromChannelProjectionOptions

Properties

PbufferSize: number
—

Maximum number of events retained in the projection snapshot.

Preplay: boolean
—

Whether to open a real subscription and receive replayed history.

View source on GitHub
property
bufferSize: number
property
onError: (error: unknown) => void
property
onEvent: (event: Event) => void
property
replay: boolean

Options for acquireChannelEffect. Extends ChannelProjectionOptions (bufferSize, replay) with the per-event callback and an optional error sink.

Maximum number of events retained in the projection snapshot. Defaults to 4096 so replay-backed discovery hooks can tolerate bursty token/media streams without dropping early lifecycle events.

Callback that is called when an error occurs.

Invoked once for every event observed while attached.

Whether to open a real subscription and receive replayed history. Defaults to true. Set false for live-only root-bus inspection when replay is unnecessary.