tdd

# TDD Skill Write the test first. Watch it fail. Write minimal code to pass. ## The Iron Law **No production code without a failing test first.** Every line of production code must be justified by a test that failed without it. No exceptions. No shortcuts. No "I'll test after." --- ## Agent Workflow ``` 1. DETECT -> Identify stack, test framework, existing test patterns 2. RED -> Write ONE failing test for the next behavior 3. VERIFY -> Run test, confirm it fails for the EXPECTED reason IF the test fails for a DIFFERENT reason (syntax error, wrong import, missing fixture) → fix the test itself and re-run. Do NOT proceed to GREEN until the failure matches the intended behavior. 4. GREEN -> Write the SIMPLEST code that makes the test pass 5. VERIFY -> Run tests, confirm ALL pass (new + existing) 6. REFACTOR -> Clean up while keeping all tests green 7. REPEAT -> Next behavior = next failing test ``` **CRITICAL**: Never skip VERIFY steps. A test that passes on first run proves nothing. --- ## RED-GREEN-REFACTOR Cycle See [references/red-green-refactor.md](references/red-green-refactor.md) for the detailed cycle with rules and verification steps. --- ## Reference Guide | Topic | Reference | |-------|-----------| | Full RED-GREEN-REFACTOR cycle | [red-green-refactor.md](references/red-green-refactor.md) | | Common mistakes and red flags | [anti-patterns.md](references/anti-patterns.md) | | Per-stack test commands | [stack-commands.md](references/stack-com...