/skill-creator — Claude Code Skill Design Guide

A Claude Code skill for creating and optimizing other Claude Code skills. Provides a 6-step creation process, bundled scaffolding scripts, and optimization principles for building production-quality skills.

Usage

/skill-creator

Then describe the skill you want to build. The skill walks you through understanding, planning, initializing, editing, packaging, and iterating.

What’s Included

skill-creator/
├── SKILL.md              ← Lean router: creation process + optimization principles
├── references/
│   └── skill-anatomy.md  ← Background: skill structure, bundled resources, progressive disclosure
├── scripts/
│   ├── init_skill.py     ← Scaffold a new skill directory
│   ├── package_skill.py  ← Validate and package a skill as .zip
│   └── quick_validate.py ← Fast validation of skill structure
└── LICENSE.txt

Skill Creation Process

Optimization Principles

The skill includes an Optimization Principles section derived from a thorough optimization pass on win4r/dev-skill. These are reusable design patterns for building high-quality skills:

Information Architecture

Position behavioral rules before reference material in SKILL.md. LLMs weight earlier content more heavily — rules buried at the bottom get forgotten.

The Router Pattern

When a skill has 3+ code paths and exceeds ~400 lines, split into a router (SKILL.md) + per-path files loaded on demand. Reduces initial context by 40-70%.

skill-name/
├── SKILL.md              ← Router: classification + shared rules
└── workflows/
    ├── path-a.md         ← Loaded via Read tool after routing
    └── path-b.md

Classification Design

For skills that classify user input: define a strict priority ordering (resolves multi-match) and disambiguation rules (resolves false positives). Test with 20-30 adversarial inputs.

Inline References

When a rule must be applied in a different section, add a reminder at the point of application. Don’t rely on the LLM to cross-reference across hundreds of lines.

Prompt Engineering Heuristics

• Keep frontmatter description under 120 characters
• Use tables for routing/lookup (O(1) for LLMs)
• Explicit “Do NOT” prohibitions in high-stakes situations
• Categorize dependencies as optional vs. required for error handling

Scaffolding Scripts

Initialize a new skill