Stream items

Stream exposes a replayable event sequence for live agent interfaces. Text deltas are the simplest consumer; the full event stream also carries reasoning, provider items, tool progress, lifecycle changes, and the final response.

stream := agent.Stream(ctx, phaseoagent.RunOptions{Input: prompt, Client: client})

for event := range stream.Events() {
  switch event.Type {
  case "response.output_text.delta":
    fmt.Print(event.Details["delta"])
  case "response.reasoning.delta":
    renderReasoning(event.Details)
  case "response.item":
    renderItem(event.Details["item"])
  case "tool.preliminary_result":
    renderProgress(event.Details)
  }
}

result, err := stream.Result()

Go currently exposes provider items through the generic AgentEvent details map rather than a closed typed item union. Switch on event.Type, validate item payloads at your UI boundary, and keep an unknown-event fallback for forward compatibility.

The event history is replayable after completion, so separate consumers can render text, persist events, and build an audit timeline without starting another model request.

Last modified on July 26, 2026

Streaming Dynamic turns

Start Here

Build

Observe

Reference