test-driven-development

Enforce a red-green-refactor cycle for feature work and bug fixes.

1|Updated Mar 27, 2026
One-click install
npx skills add https://github.com/minfengyuan/harness-knowledge-base --skill test-driven-development-minfengyuan
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: test-driven-development
Source: https://github.com/minfengyuan/harness-knowledge-base/tree/main/skills/test-driven-development
Command: npx skills add https://github.com/minfengyuan/harness-knowledge-base --skill test-driven-development-minfengyuan

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Implementing features or bug fixes without tests often leads to regressions and unclear expectations. This skill enforces a test-first mindset to clarify requirements and provide a safety net before coding.

Core Features & Use Cases

  • Red-Green-Refactor workflow to guide development from failing tests to passing code and subsequent cleanup
  • Prevents regressions by forcing tests to prove behavior before implementation
  • Suitable for new features, bug fixes, and refactoring tasks with clear success criteria

Quick Start

Apply TDD by writing a failing test first, then implement the minimal code to pass, and refactor for readability.

Frequently Asked Questions about test-driven-development

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

FAQPage Schema
How do I start writing tests before implementation code?▼

Writing tests before implementation code requires a red-green-refactor cycle: write a failing test first, implement the minimal code to pass it, then refactor for readability. This clarifies requirements and provides a safety net before coding.

What is the red-green-refactor workflow for test-driven development?▼

The red-green-refactor workflow drives development from failing tests to passing code and subsequent cleanup. You write a failing test, implement minimal code to pass, then refactor for clean, well-factored code.

Can I use test-first development for both new features and bug fixes?▼

Yes, test-first development suits both new features and bug fixes. It enforces a fail-first mindset to clarify expectations and prevents regressions by proving behavior before implementation.

Why does writing code without tests lead to regressions?▼

Writing code without tests leads to regressions because expectations remain unclear and unverified. Enforcing a test-first mindset clarifies requirements and provides a safety net before coding.

What's the best way to prevent regressions when fixing bugs?▼

The best way to prevent regressions when fixing bugs is enforcing a test-first approach. Forcing tests to prove behavior before implementation ensures minimal, clean code and prevents future regressions.