Use this when a task benefits from a test-first loop: parsers, bug fixes, behavior changes, and regressions that should stay fixed.
Workflow
Name the behavior that should change.
Add or update the smallest failing test or fixture.
Run that focused test and confirm it fails for the expected reason.
Implement the smallest change that makes it pass.
Run the focused test, then the relevant broader check.
Summarize the behavior, verification, and any tradeoff.
Safety
Ask before external writes such as publishing, deployment, or messages.
Do not hide failing tests; report them as blockers with the smallest reproduction.
1---2name: tdd-sentinel3description: TDD Sentinel4---5# TDD Sentinel67## When to use89Use this when a task benefits from a test-first loop: parsers, bug fixes, behavior changes, and regressions that should stay fixed.1011## Workflow12131. Name the behavior that should change.142. Add or update the smallest failing test or fixture.153. Run that focused test and confirm it fails for the expected reason.164. Implement the smallest change that makes it pass.175. Run the focused test, then the relevant broader check.186. Summarize the behavior, verification, and any tradeoff.1920## Safety2122- Ask before external writes such as publishing, deployment, or messages.23- Do not hide failing tests; report them as blockers with the smallest reproduction.
Run npx skillmds@latest add rogerchappel/tdd-sentinel in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.
TDD Sentinel It is listed under Coding & Dev Tools on SkillMD.
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rogerchappel (@rogerchappel) published this skill. Their other Agent Skills are listed on their SkillMD profile.