| name | spec-first |
| description | Write the goal spec on disk before the agent acts, so it can't drift. Use before any multi-step task. |
| when_to_use | a task with more than 2 steps, a long-running job, "build X", agent drifting |
Spec First
Without an external contract, the agent drifts after ~3 iterations — and the failure looks like progress (code written, tests pass, wrong goal solved).
Write PROMPT.md BEFORE acting:
- Goal — one sentence.
- Done when — concrete, checkable conditions. "Test suite green: ".
- Never touch — files/areas off-limits.
- Stop if — more than N files outside scope change; a passing test starts failing.
The agent re-reads this file every iteration. State (what's done) goes in a separate
IMPLEMENTATION_PLAN.md it updates in place. If you can't write "done when" concretely, the task isn't ready — clarify before coding.