| name | test-backed-change |
| description | Add or update behavior-focused tests for code changes and run appropriate verification. Use when behavior changes, logic is added, or existing behavior could regress. |
Test-Backed Change
Use this skill whenever implementation changes behavior.
Read templates/test-proof.md when reporting verification evidence.
Workflow
- Identify the behavior being changed.
- Find the existing test style and test level for that behavior.
- Add or update the smallest test that would fail if the behavior regressed.
- Prefer public interfaces and observable behavior over implementation
details.
- Run the targeted test first.
- Run broader tests when touched surface, shared code, or risk justifies it.
- Report exact commands and results.
Guardrails
- Do not add tests that only assert implementation details.
- Do not delete or weaken failing tests to make the suite pass.
- Do not claim behavior is verified when only typecheck or lint ran.
- If no test can be added reasonably, explain why and provide the strongest
available alternative evidence.
Output
Test Proof
- behavior:
- test:
- command:
- result:
- remaining gap:
