tdd-guide (Codex Compatibility)

SkillDev tools

Guides your agent to write failing tests first and build code through the RED, GREEN, REFACTOR cycle.

Instructions available. Your AI can read the instructions. Execution depends on the setup they require.

Account requirements not reviewed. Check the skill instructions before use; ahel provides instructions and does not run this skill.

Add ahel to your AI once: Claude, ChatGPT, Cursor, Claude Code or Codex. Then ask it to use this.

Then ask your AI: use the tdd-guide (Codex Compatibility) skill

About this skill

Test-first development route for TDD, writing failing tests first, RED -> GREEN -> REFACTOR, and behavior-changing feature/bug/refactor work. Do not use for already-failing test root-cause debugging, test-report packaging, or final completion evidence.

What this skill tells your AI

The instructions your AI receives, as published by foryourhealth111-pixel/vibe-skills in bundled/skills/tdd-guide/SKILL.md and read by ahel’s review.

Use this skill for all feature work, bug fixes, and refactors that change behavior.

Routing Boundary

Use this skill when the user wants to build or change behavior through tests:

TDD / test-driven development
write failing tests first
test-first implementation
RED -> GREEN -> REFACTOR

Do not use it when tests are already failing and the user wants root cause; route that to systematic-debugging. Do not use it when the user only wants a test/coverage report; route that to generating-test-reports.

Core Rule

No production code before a failing test.

Workflow

Write one failing test for one behavior.
Confirm the failure is expected.

GREEN

Implement the minimal code to pass.
Re-run tests and keep scope narrow.

REFACTOR

Improve structure/naming without changing behavior.
Keep all tests green.

COVERAGE

Verify coverage target (recommended >=80% for lines/functions/branches).
Add missing tests for edge/error paths.

Minimum Test Set

Unit: public functions and core logic.
Integration: API/data/service boundaries.
E2E: critical user path only when relevant.

Required Edge Cases

Null/undefined input
Empty values
Invalid types
Boundary values
Error paths (network/DB/file)
Concurrency-sensitive behavior

Vibe Integration

Primary coding skill in M-grade flow.
Compatible fallback target for everything-claude-code:tdd-guide.
For richer TDD patterns, combine with test-driven-development.

Signals

GitHub stars: 4k
Forks: 308
Last commit: Aug 2026

Advanced

Item type: skill
Key: tdd-guide-foryourhealth111-pixel
Source: github.com/foryourhealth111-pixel/vibe-skills

github.com/foryourhealth111-pixel/vibe-skills