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

# Stream

> Enable streaming and handle text deltas and tool lifecycle events on an AgentEvent channel

Agent configured with `WithStream(true)` that emits lifecycle events as the loop runs — text deltas, tool calls, run finished.

Source: [`examples/agent_with_stream/`](https://github.com/agenticenv/agent-sdk-go/tree/main/examples/agent_with_stream)

## What it demonstrates

* `Stream()` returning `<-chan AgentEvent`
* Handling `TEXT_MESSAGE_CONTENT`, tool lifecycle events, and `RUN_FINISHED`
* Built-in tools with auto-approval

## Run

From `examples/`:

```bash theme={null}
go run ./agent_with_stream "What's the weather in Tokyo?"
go run ./agent_with_stream "What is 15 + 27?"
```

## Key code

Enable streaming at construction, then consume the event channel:

```go theme={null}
a, err := agent.NewAgent(
    agent.WithLLMClient(llmClient),
    agent.WithStream(true),
    agent.WithToolRegistry(reg),
    agent.WithToolApprovalPolicy(agent.AutoToolApprovalPolicy()),
)

eventCh, err := a.Stream(ctx, prompt, nil)
if err != nil {
    log.Fatal(err)
}
for ev := range eventCh {
    if ev == nil {
        continue
    }
    switch ev.Type() {
    case agent.AgentEventTypeTextMessageContent:
        if t, ok := ev.(*agent.AgentTextMessageContentEvent); ok {
            fmt.Print(t.Delta)
        }
    case agent.AgentEventTypeRunFinished:
        // result and LLMUsage available on AgentRunFinishedEvent.Result
    case agent.AgentEventTypeRunError:
        if t, ok := ev.(*agent.AgentRunErrorEvent); ok {
            log.Println("error:", t.Message)
        }
    }
}
```

See [Streaming](/getting-started/streaming) for all event types and [AG-UI Protocol](/features/ag-ui-protocol) for frontend integration.

## Expected output

Tokens print to stdout as they arrive, with no trailing newline until the run finishes:

```
The current weather in Tokyo is 18°C, partly cloudy with light winds from the northeast.
```

With `SHOW_LLM_USAGE=true` a usage footer follows on a new line. Tool lifecycle events are consumed silently in this example — add a `case` for `AgentEventTypeToolCallStart` to log them.

## Learn more

<CardGroup cols={2}>
  <Card title="Streaming" icon="wave-pulse" href="/getting-started/streaming">
    Event types and consumption patterns
  </Card>

  <Card title="Stream + Conversation" icon="messages" href="/examples/stream-conversation">
    Streaming with persisted history
  </Card>

  <Card title="AG-UI" icon="diagram-project" href="/examples/agui">
    SSE server for web frontends
  </Card>
</CardGroup>