> ## Documentation Index
> Fetch the complete documentation index at: https://phaseo.app/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Streaming

> Stream text, reasoning, tool activity, and complete agent events.

Use `stream()` when your interface should show an agent's response or tool activity while the run is still in progress. It starts the same resumable state machine as `run()` with a streaming model client.

## Stream text

```typescript theme={null}
const result = agent.stream({ input, client });

for await (const delta of result.getTextStream()) {
  process.stdout.write(delta);
}

const completed = await result.getResult();
console.log(completed.run.status);
```

## Read the result in more than one place

Stream consumers are replayable, so rendering, telemetry, and persistence code can consume the same run concurrently:

```typescript theme={null}
const result = agent.stream({ input, client });

const [text, completed] = await Promise.all([
  result.getText(),
  result.getResult(),
]);
```

## Choose a stream

* `getTextStream()` yields answer text.
* `getReasoningStream()` yields reasoning updates when the model provides them.
* `getItemsStream()` yields typed `AgentItem<TOutput>` values for messages, reasoning, tool activity, errors, and final outputs.
* `getToolStream()` yields tool activity.
* `getFullStream()` yields complete runtime events.

Use `cancel()` to abort the run. Local tools receive cancellation through their runtime signal.

## Stream tool progress

Tools implemented as async generators can publish preliminary results. These appear in the full stream as `tool.preliminary_result` events and remain attached to the completed step.

```typescript theme={null}
const indexRepository = defineTool({
  id: "index-repository",
  async *execute(input: { path: string }) {
    yield { phase: "scan" };
    yield { phase: "embed" };
    return { indexed: 248 };
  },
});
```

## Related guides

* [Define and run tools](./agent-sdk-tools)
* [Work with typed items](./agent-sdk-items)
* [Lifecycle hooks](./agent-sdk-lifecycle-hooks)
* [Build a durable agent loop](../../cookbook/agent-sdk-durable-loop.mdx)