Can I use this for existing codebases?

Yes, it is ideal for fixing bugs or adding features to existing projects by first defining the target behavior through a focused test case.

What happens if a test doesn't fail initially?

The skill includes a 'fail fast' gate; if a test doesn't fail as expected (Red), Claude will stop to investigate the environment or specification before proceeding.

Why use TDD with an AI agent like Claude?

TDD provides a concrete 'definition of done' and objective proof of correctness, which significantly reduces the risk of AI logic errors and hallucinations.

How does this skill handle the 'Red' phase?

It requires writing and running a failing test to verify the expected behavior change or bug reproduction before any production code is modified.

Does it support all testing frameworks?

Yes, it is framework-agnostic. It adapts to the specific test commands and repository structures defined in your local environment.

Test-Driven Development (TDD)

Name: Test-Driven Development (TDD)
Author: jscraik

byjscraik

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Security & Testing

Implements high-confidence code changes using the Red-Green-Refactor cycle to ensure every behavior is verified by tests before implementation.

This skill equips Claude with a rigorous Test-Driven Development (TDD) workflow, forcing a 'test-first' approach to feature development and bug fixing. By strictly adhering to the Red-Green-Refactor cycle, it ensures that every code change is backed by executable evidence, preventing regressions and reducing rework. It is particularly effective for complex logic where behavior must be precisely defined and verified, providing a clear audit trail of failing and passing tests to guarantee production-grade reliability and maintainability.

Key Features

01Automated verification of failing tests before implementation

02Evidence-based reporting of test transitions and outcomes

03Regression checking across related test suites

04Minimalist code changes focused on passing specific test cases

05Strict Red-Green-Refactor workflow execution

062 GitHub stars

Use Cases

01Fixing regressions by creating a reproduction test first

02Refactoring critical legacy code with safety gates

03Implementing new features with complex business logic

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add jscraik/agent-skills test-driven-development

For use in Claude.ai and ChatGPT

Key Features

01Automated verification of failing tests before implementation

02Evidence-based reporting of test transitions and outcomes

03Regression checking across related test suites

04Minimalist code changes focused on passing specific test cases

05Strict Red-Green-Refactor workflow execution

062 GitHub stars

Use Cases

01Fixing regressions by creating a reproduction test first

02Refactoring critical legacy code with safety gates

03Implementing new features with complex business logic

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add jscraik/agent-skills test-driven-development

For use in Claude.ai and ChatGPT