Method●Since v1.0

stream

stream<
  TStreamMode extends StreamMode | StreamMode[] | undefined,
  TSubgraphs extends boolean

View source on GitHub

Parameters

Name	Type	Description
`state`*	`InvokeStateParameter<Types>`	The initial state for the agent execution. Can be: An object containing `messages` array and any middleware-specific state properties A Command object for more advanced control flow
`config`	`StreamConfiguration<InferContextInput<Types["Context"] extends InteropZodObject \| AnyAnnotationRoot ? any[any] : AnyAnnotationRoot> & InferMiddlewareContextInputs<Types["Middleware"]>, TStreamMode, TSubgraphs, TEncoding>`

Example

const agent = new ReactAgent({
  llm: myModel,
  tools: [calculator, webSearch]
});

const stream = await agent.stream({
  messages: [{ role: "human", content: "What's 2+2 and the weather in NYC?" }]
});

for await (const chunk of stream) {
  console.log(chunk); // State update from each node
}

Executes the agent with streaming, returning an async iterable of state updates as they occur.

This method runs the agent's workflow similar to invoke, but instead of waiting for completion, it streams high-level state updates in real-time. This allows you to:

Display intermediate results to users as they're generated
Monitor the agent's progress through each step
React to state changes as nodes complete

For more granular event-level streaming (like individual LLM tokens), use streamEvents instead.

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Parameters

Example