> ## 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.

# Dynamic turns

> Change Python model settings and tools between agent turns.

Model, fallback models, instructions, temperature, maximum output tokens, top-p, and tools can be fixed values or callbacks evaluated for each turn.

Use `runtime.set_context(value)` when a tool discovers information needed later. Use `next_turn_params` for an override that applies only to the immediately following model request.

Next-turn overrides are saved with paused state, so an approval checkpoint does not discard the routing or sampling decision.

Keep context serializable when using `AgentStateAccessor`.

## Related

* [Tools](./agent-sdk-tools)
* [State and approval](./agent-sdk-state-and-approval)
* [Stop conditions](./agent-sdk-stop-conditions)