Dynamic turns

Dynamic turn callbacks let routing react to run state without rebuilding the agent. They run before each model request and receive the current turn context.

agent := phaseoagent.CreateAgent(phaseoagent.AgentDefinition{
  ID: "support-agent",
  DynamicModel: func(turn phaseoagent.TurnContext) string {
    if turn.Run.StepCount > 3 { return "openai/gpt-5.4" }
    return "openai/gpt-5.4-nano"
  },
  DynamicInstructions: func(turn phaseoagent.TurnContext) string {
    return fmt.Sprintf("Resolve the request. Current context: %v", turn.Context)
  },
})

You can also configure dynamic tools and per-turn Temperature, MaxOutputTokens, and TopP values.

Let a tool influence the next turn

Set NextTurn on a tool to change the immediately following model request. These overrides are stored in paused state, so they survive an approval checkpoint, and expire after the next turn. Use dynamic callbacks for policy that should be recalculated every turn. Use NextTurn for a tool-specific handoff such as switching models after repository inspection.

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Let a tool influence the next turn

​Let a tool influence the next turn

Let a tool influence the next turn