Use when writing tests before implementation, applying red-green-refactor or reviewing test-first development. Not for Vitest APIs or request mocking; use vitest or msw.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Community Test-Driven Development Best Practices
Comprehensive guide to Test-Driven Development practices, designed for AI agents and LLMs. Contains 42 rules across 8 categories, prioritized by impact to guide test writing, refactoring, and code generation.
## When to Apply
Reference these guidelines when:
- Writing new tests using TDD workflow
- Implementing the red-green-refactor cycle
- Designing test structure and organization
- Creating test data and fixtures
- Reviewing or refactoring existing test suites
## TDD Workflow
1. **RED**: Write a failing test that defines desired behavior
2. **GREEN**: Write minimal code to make the test pass
3. **REFACTOR**: Clean up code while keeping tests green
4. Repeat for each new behavior
## Rule Categories by Priority
| Priority | Category | Impact | Prefix |
|----------|----------|--------|--------|
| 1 | Red-Green-Refactor Cycle | CRITICAL | `cycle-` |
| 2 | Test Design Principles | CRITICAL | `design-` |
| 3 | Test Isolation & Dependencies | HIGH | `isolate-` |
| 4 | Test Data Management | HIGH | `data-` |
| 5 | Assertions & Verification | MEDIUM | `assert-` |
| 6 | Test Organization & Structure | MEDIUM | `org-` |
…
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Source
GitHub
cratis/ai · 4 stars · license MIT · pushed 2026-11-04 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_y5tg6sohsk4nb6ii
GET https://markdownregistry.com/api/v1/resolve?ref=cratis/ai/tdd
GET https://markdownregistry.com/api/v1/blob/262579374f51bf659fd462576cc0d244444dd72bcbceeede6c55578c11844ad3
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