Test Driven Development

This consolidates TDD patterns into a single reusable skill so you don't need to repeat testing guidance across multiple agents. It covers the red-green-refactor cycle, test structure patterns like AAA and Given-When-Then, and language-specific examples for Python, JavaScript, and Go. The naming conventions and mock patterns are solid reference material. Most useful when you're setting up a new project or want consistent testing practices across a codebase. The anti-patterns section is honest about common mistakes like testing implementation details or running slow tests in your unit suite. Saves you from writing the same 500 lines of testing docs every time you spin up a new agent.

skills.sh installs: 400
GitHub stars: 79
last updated: Aug 21, 2026

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Install

$ npx -y skills add bobmatnyc/claude-mpm-skills --skill test-driven-development --agent claude-code

Installs into .claude/skills of the current project.

Files

Test-Driven Development (TDD)

Comprehensive TDD patterns and practices for all programming languages. This skill eliminates ~500-800 lines of redundant testing guidance per agent.

When to Use

Apply TDD for:

New feature implementation
Bug fixes (test the bug first)
Code refactoring (tests ensure behavior preservation)
API development (test contracts)
Complex business logic

TDD Workflow (Red-Green-Refactor)

1. Red Phase: Write Failing Test

Write a test that:
- Describes the desired behavior
- Fails for the right reason (not due to syntax errors)
- Is focused on a single behavior

2. Green Phase: Make It Pass

Write the minimum code to:
- Pass the test
- Not introduce regressions
- Follow existing patterns

3. Refactor Phase: Improve Code

While keeping tests green:
- Remove duplication
- Improve naming
- Simplify logic
- Extract functions/classes

Test Structure Patterns

Arrange-Act-Assert (AAA)

// Arrange: Set up test data and conditions
const user = createTestUser({ role: 'admin' });

// Act: Perform the action being tested
const result = await authenticateUser(user);

SKILL.md on GitHub