writing-skills

<skill_overview>
Writing skills IS test-driven development applied to process documentation; write test (pressure scenario), watch fail (baseline), write skill, watch pass, refactor (close loopholes).
</skill_overview>

<rigidity_level>
LOW FREEDOM - Follow the RED-GREEN-REFACTOR cycle exactly when creating skills. No skill without failing test first. Same Iron Law as TDD.
</rigidity_level>

<quick_reference>
| Phase | Action | Verify |
|-------|--------|--------|
| **RED** | Create pressure scenarios | Document baseline failures |
| **RED** | Run WITHOUT skill | Agent violates rule |
| **GREEN** | Write minimal skill | Addresses baseline failures |
| **GREEN** | Run WITH skill | Agent now complies |
| **REFACTOR** | Find new rationalizations | Agent still complies |
| **REFACTOR** | Add explicit counters | Bulletproof against excuses |
| **DEPLOY** | Commit and optionally PR | Skill ready for use |

**Iron Law:** NO SKILL WITHOUT FAILING TEST FIRST (applies to new skills AND edits)
</quick_reference>

<when_to_use>
**Create skill when:**
- Technique wasn't intuitively obvious to you
- You'd reference this again across projects
- Pattern applies broadly (not project-specific)
- Others would benefit from this knowledge

**Never create for:**
- One-off solutions
- Standard practices well-documented elsewhere
- Project-specific conventions (put in CLAUDE.md instead)

**Edit existing skill when:**
- Found new rationalization agents use
- Discovered loophole in current guidance
- Need to add clarifying examples

**ALWAYS test before writing or editing. No exceptions.**
</when_to_use>

<tdd_mapping>
Skills use the exact same TDD cycle as code:

| TDD Concept | Skill Creation |
|-------------|----------------|
| **Test case** | Pressure scenario with subagent |
| **Production code** | Skill document (SKILL.md) |
| **Test fails (RED)** | Agent violates rule without skill |
| **Test passes (GREEN)** | Agent complies with skill present |
| **Refactor** | Close loopholes while