Test-Driven Development

Test-Driven Development is a Quality skill for Claude Code, published by majiayu000 in spellbook.

265 stars26 forkson majiayu000/spellbookAdded 2026/09/02+1% in starsRepository updated 2026/08/31

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Install in seconds

Install Test-Driven Development

Copy Test-Driven Development into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/majiayu000/spellbook/tree/main/skills ~/.claude/skills/skills

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/majiayu000/spellbook.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: skills/test-driven-development.SKILL.md in majiayu000/spellbook
Installs to: ~/.claude/skills/skills
Collection: One of 25 skills cataloged from this repository
Category: Quality — 1418 skills

What Test-Driven Development does

Test-Driven Development enforces writing a failing test before implementation, then using the red-green-refactor cycle to build and change code safely. Use it for new features, bug fixes, and refactors.

Test-Driven Development is cataloged under Quality on DirSkills. Test-Driven Development comes from a repository tagged agent-skills, ai-agent-skills, ai-agents, ai-coding-assistant and automation.

Documentation

README

Excerpt

Test-Driven Development (TDD)

From obra/superpowers

Core Principle

Write tests before implementation. Watch them fail. Write minimal code to pass.

THE IRON LAW: NO PRODUCTION CODE WITHOUT A FAILING TEST FIRST

When to Apply TDD

New features
Bug fixes
Refactoring
Any behavior changes

The Red-Green-Refactor Cycle

RED: Write a Failing Test

Write ONE minimal test demonstrating desired behavior
Use clear, descriptive test names
Use real code, avoid unnecessary mocks
Test should fail for the RIGHT reason

# Verify RED
- Run the test
- Confirm it fails
- Confirm failure is NOT due to syntax errors
- Confirm you're not testing existing functionality

GREEN: Make It Pass

This is the opening of the README. Read the full README on GitHub.

Frequently asked about Test-Driven Development

What else does majiayu000 publish alongside Test-Driven Development?
Test-Driven Development is one of 25 skills that DirSkills catalogs from majiayu000/spellbook, the repository it ships in. Its siblings there include AGENTS.md Scaffold, API Design and Agents Md Optimize. Each one is a separate skill with its own page in this directory, installs the same way Test-Driven Development does, and is maintained by majiayu000 in that same repository. The rest of the collection is listed on the majiayu000/spellbook page.
How does Test-Driven Development compare to other Quality skills?
Test-Driven Development ranks #1272 by stars among the 1418 Quality skills in this catalog. The most-starred ones next to it are Benchmark, Benchmark Optimization Loop and API Design Patterns. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of Test-Driven Development against them. Open each page to compare what they document and how they install.