--- name: skill-creator description: Guide for creating effective skills. Use when users want to create a new skill (or update an existing skill) that extends Claude's capabilities with specialized knowledge, workflows, or tool integrations. source: anthropics/skills license: Apache-2.0 --- # Skill Creator Skills are modular packages that extend Claude's capabilities by providing specialized knowledge, workflows, and tools. ## Core Principles ### Concise is Key The context window is a shared resource. Only add context Claude doesn't already have. Challenge each piece: "Does Claude really need this?" ### Anatomy of a Skill ``` skill-name/ ├── SKILL.md (required) │ ├── YAML frontmatter (name, description) │ └── Markdown instructions └── Bundled Resources (optional) ├── scripts/ - Executable code ├── references/ - Documentation └── assets/ - Templates, images ``` ### SKILL.md Format ```markdown --- name: my-skill-name description: A clear description of what this skill does and when to use it --- # My Skill Name [Instructions for Claude when this skill is active] ## Examples - Example usage 1 - Example usage 2 ## Guidelines - Guideline 1 - Guideline 2 ``` ## Skill Creation Process ### Step 1: Understand with Examples Gather concrete examples of how the skill will be used. Ask: - "What functionality should this skill support?" - "What would a user say that should trigger this skill?" ### Step 2: Plan Reusable Contents Analyze examples to identify: - **Scripts**: Code that gets rewritten repeatedly - **References**: Documentation Claude needs to reference - **Assets**: Templates, images for output ### Step 3: Initialize Create the skill directory structure with SKILL.md and resource folders. ### Step 4: Implement - Start with reusable resources (scripts, references, assets) - Write clear SKILL.md with proper frontmatter - Test scripts by actually running them ### Step 5: Iterate Use the skill on real tasks, notice struggles, improve. ## Progressive Disclosure Keep SKILL.md under 500 lines. Split content: ```markdown # PDF Processing ## Quick start [code example] ## Advanced features - **Form filling**: See [FORMS.md](FORMS.md) - **API reference**: See [REFERENCE.md](REFERENCE.md) ``` ## What NOT to Include - README.md - INSTALLATION_GUIDE.md - CHANGELOG.md - User-facing documentation Skills are for AI agents, not humans.