test-driven-development

Enforces red-green-refactor test-first workflow for implementing features and bugfixes.

1|Updated Jun 6, 2026

Search Tags:#unit tests #testing #tdd #refactoring #bug fixing #red-green-refactor #test-first

Ready to run

npx skills add https://github.com/JaimeHoracio/Ostacky --skill test-driven-development-jaimehoracio

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: test-driven-development
Source: https://github.com/JaimeHoracio/Ostacky/tree/main/assets/skills/tdd
Command: npx skills add https://github.com/JaimeHoracio/Ostacky --skill test-driven-development-jaimehoracio

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve? It prevents untested production code by enforcing a strict test-first discipline, ensuring every feature or bugfix is backed by a failing test that was observed before implementation. ## Core Features & Use Cases - Red-Green-Refactor Cycle: Guides writing a failing test, verifying the failure, writing minimal passing code, and refactoring safely. - Rationalization Detection: Lists common excuses for skipping TDD and explains why each leads to unreliable code. - Verification Checklist: Provides a completion checklist covering failing-test verification, minimal implementation, and pristine test output. - Use Case: When fixing a bug where an empty email is accepted, write a failing test asserting the rejection, watch it fail, implement the minimal validation, and confirm all tests pass. ## Quick Start Ask the agent to implement a new feature or fix a bug using test-driven development with a failing test written first.

Frequently Asked Questions about test-driven-development

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I practice test-driven development on a new feature?▼

Write one minimal failing test describing the desired behavior, run it to confirm it fails for the right reason, then write the simplest code that makes it pass. Refactor only while tests stay green, then repeat for the next behavior.

How do I fix a bug using TDD?▼

Write a failing test that reproduces the bug first, then implement the minimal fix until the test passes. This proves the fix works and creates a regression test that prevents the bug from returning.

Why must I watch the test fail before writing code?▼

A test that passes immediately proves nothing, since it may test the wrong thing or existing behavior. Watching it fail confirms the test actually exercises the missing feature and would catch the bug.

When is it acceptable to skip test-driven development?▼

Exceptions are limited to throwaway prototypes, generated code, and configuration files, and only with explicit approval from your human partner. Exploration is allowed, but the exploratory code must be discarded before restarting with TDD.

What should I do if I already wrote code before the test?▼

Delete the implementation and start over with a failing test. Keeping it as reference or adapting it biases the tests toward the implementation, which defeats the purpose of test-first development.