# TurnHook

**Kind:** Interface

**Source:** [`atloria-monorepo/libs/agent-core/src/runtime/types.ts`](https://github.com/sherkety/atloria/blob/main/atloria-monorepo/libs/agent-core/src/runtime/types.ts#L274)

Hook invoked before each model call within the agent loop.
Allows domain layers to:
- Inject runtime state into instructions (turn budget, progress, tool result summaries)
- Monitor context pressure and warn the agent
- Track turn progression

Implemented by domain layers (e.g., PmeTurnHook), wired in agent-runtime.ts
via the SDK's callModelInputFilter.