test-driven-development

An agent skill by addyosmani, from addyosmani/agent-skills. Tags: api, debugging, developer-tools.

What it does

Drives development with tests using the red-green-refactor loop. Use when implementing any logic, fixing any bug, or changing any behavior. Use when you need to prove that code works, when a bug report arrives, or when you're about to modify existing functionality.

Install

With the skills CLI, which installs into Claude Code, Codex, Cursor and other agents:

npx skills add addyosmani/agent-skills --skill test-driven-development

Or copy the skill folder into Claude Code's skills directory by hand (~/.claude/skills for every project, or .claude/skills inside one):

git clone --depth 1 https://github.com/addyosmani/agent-skills
cp -r agent-skills/skills/test-driven-development ~/.claude/skills/test-driven-development

Safety box score

Not rated yet. A safety box score grades what a skill and its scripts can reach on the machine of whoever installs it, across eight categories from shell execution to secrets access. Anyone can request one from this page; it is saved for everyone. How the score works.

Source

Repository

addyosmani/agent-skills (all skills from this repository)

Path

skills/test-driven-development/SKILL.md

Branch

main

Updated

2026-09-19

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• security-and-hardening — Hardens code against vulnerabilities.
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