# Policy: Model routing

Use model by task complexity, not by habit.

## Core rule
- Start small.
- Escalate only when blocked or quality poor.

## Escalation triggers
- Repeated failed attempts.
- Ambiguous requirements.
- Cross-module side effects.
- Security-critical code paths.

## De-escalation triggers
- Routine CRUD edits.
- Mechanical refactors.
- Artifact writing.
- Status/timeline updates.

## Required behavior
- Record chosen model class in artifact header when work is non-trivial.
- Keep outputs concise to reduce token burn.
- If `harness/project.config.json` has `model_mode=lean`, prefer tiny/small whenever possible.