Is refactoring allowed during the Red phase?

No, refactoring is strictly permitted only during the Refactor phase after the code has reached a Green (passing) state.

What happens if a test passes immediately during the Red phase?

The skill flags this as a Red Flag, requiring you to delete the code and start over to ensure the test is actually verifying functionality.

What is the 'Iron Law' enforced by this skill?

The Iron Law dictates that no production code should be written unless a test has first been written and observed to fail.

How does this skill handle 'minimal code' requirements?

It restricts the developer from adding extra features or complexity beyond what is strictly necessary to make the current failing test pass.

Can I use this for fixing bugs?

Yes, the skill requires you to write a failing test that reproduces the bug before implementing any fix to ensure the solution works as expected.

TDD Discipline

Name: TDD Discipline
Author: gvarela

bygvarela

0•

Security & Testing

Enforces a strict Red-Green-Refactor cycle by requiring a failing test before any production code is implemented.

The TDD Discipline skill transforms Claude into a rigorous pair programmer that adheres to the core tenets of Test-Driven Development. By mandating the 'Iron Law'—no production code without a prior failing test—this skill ensures that every line of code is purposeful, verified, and maintainable. It guides the AI through the Red-Green-Refactor phases, preventing feature creep and ensuring that failing tests are legitimate indicators of missing functionality rather than configuration errors or typos. This skill is ideal for teams and developers who prioritize code quality and want to eliminate technical debt from the outset.

Key Features

01Guides developers through the complete Red-Green-Refactor cycle

02Enforces the 'Iron Law' of no production code without a failing test

03Provides structured refactoring guidance once code is in a green state

04Prevents over-engineering by focusing on minimal code to pass tests

050 GitHub stars

06Validates failure messages to ensure tests catch the correct logic gaps

Use Cases

01Modernizing legacy codebases through systematic, test-verified updates

02Debugging and fixing bugs by reproducing them first with failing test cases

03Implementing new features with high reliability and zero-regression goals

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add gvarela/prompts tdd-discipline

For use in Claude.ai and ChatGPT

Download Skill