writing-skills

Test-driven documentation for creating reusable agent techniques, patterns, and reference guides.

- Write failing test scenarios first (baseline agent behavior without skill), then write minimal skill documentation to address specific violations, following RED-GREEN-REFACTOR cycle

- Skills live in agent-specific directories and must include YAML frontmatter (name, description), overview, core patterns, quick reference, and common mistakes sections

- Description field must start with "Use when..." and list only triggering conditions-never summarize workflow, as Claude may follow description instead of reading full skill content

- Requires understanding superpowers:test-driven-development; discipline-enforcing skills need explicit loophole closures and rationalization tables to resist workarounds under pressure

- Keep getting-started skills under 150 words, other frequently-loaded skills under 200 words total; use cross-references and tool help to compress token usage

Writing Skills

Overview

Writing skills IS Test-Driven Development applied to process documentation.

Personal skills live in agent-specific directories (~/.claude/skills for Claude Code, ~/.agents/skills/ for Codex)

You write test cases (pressure scenarios with subagents), watch them fail (baseline behavior), write the skill (documentation), watch tests pass (agents comply), and refactor (close loopholes).

Core principle: If you didn't watch an agent fail without the skill, you don't know if the skill teaches the right thing.

REQUIRED BACKGROUND: You MUST understand superpowers:test-driven-development before using this skill. That skill defines the fundamental RED-GREEN-REFACTOR cycle. This skill adapts TDD to documentation.

Official guidance: For Anthropic's official skill authoring best practices, see anthropic-best-practices.md. This document provides additional patterns and guidelines that complement the TDD-focused approach in this skill.

What is a Skill?

A skill is a reference guide for proven techniques, patterns, or tools. Skills help future Claude instances find and apply effective approaches.