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Reference: Run.observeStream() | Streaming

docs/src/content/en/reference/streaming/workflows/observeStream.mdx

2025-12-181.1 KB
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Run.observeStream()

The .observeStream() method opens a new ReadableStream to a workflow run that's currently running, allowing you to observe the stream of events if the original stream is no longer available.

Usage example

typescript
const run = await workflow.createRun()

run.stream({
  inputData: {
    value: 'initial data',
  },
})

const stream = await run.observeStream()

for await (const chunk of stream) {
  console.log(chunk)
}

Returns

ReadableStream<ChunkType>

Stream events

The stream emits various event types during workflow execution. Each event has a type field and a payload containing relevant data:

  • workflow-start: Workflow execution begins
  • workflow-step-start: A step begins execution
  • workflow-step-output: Custom output from a step
  • workflow-step-result: A step completes with results
  • workflow-finish: Workflow execution completes with usage statistics