SKILL.md files with YAML frontmatter. This format follows the Agent Skills specification for cross-agent compatibility.
Basic Structure
A skill consists of a markdown file with YAML frontmatter:YAML Frontmatter Schema
The frontmatter contains metadata that helps agents discover and understand your skill.Required Fields
Unique identifier for the skill. Must be lowercase with hyphens (kebab-case).Examples:
frontend-designpr-review-helperdeploy-to-vercel
Brief explanation of what the skill does and when to use it. This appears in skill listings and helps agents decide when to activate the skill.Best practices:
- Keep it concise (1-2 sentences)
- Focus on the “what” and “when”
- Mention key capabilities or use cases
Optional Fields
Additional metadata for skill behavior and visibility.Subfields:
Set to
true to hide the skill from normal discovery. Internal skills are only visible when INSTALL_INTERNAL_SKILLS=1 is set.Use cases:- Work-in-progress skills
- Internal tooling not meant for public use
- Experimental features under development
Markdown Content
The body of theSKILL.md file contains instructions for the agent. Use standard markdown formatting.
Recommended Sections
Skill Title
Skill Title
A clear, descriptive title (H1) that matches or expands on the skill name.
When to Use
When to Use
Describe scenarios where this skill should be activated.
Instructions / Steps
Instructions / Steps
Detailed instructions for the agent to follow.
Examples
Examples
Code examples or templates (optional but helpful).
Resources
Resources
Links to relevant documentation or tools (optional).
Complete Example
Here’s a complete example of a well-structured skill:Resources
.claude-plugin/plugin.json
Similar structure for individual plugin definitions.
Skills discovered via plugin manifests are associated with their parent plugin, making it easy to group related skills.
Best Practices
Keep it focused
Each skill should do one thing well. Create multiple focused skills rather than one large skill.
Be specific
Provide concrete instructions and examples. Avoid vague guidance like “follow best practices.”
Use sections
Organize instructions with clear headings and numbered steps. This helps agents parse and follow the guidance.
Test thoroughly
Test your skill with your target agent to ensure it works as expected. Different agents may interpret instructions differently.
Validation Rules
The Skills CLI validates skills during discovery:Frontmatter must be valid YAML
Use a YAML validator to check syntax. Common issues:
- Missing closing quotes
- Incorrect indentation
- Invalid special characters
Required fields must exist
Both
name and description must be present and be strings (not numbers or booleans).Internal Skills
Skills can be hidden from normal discovery:Creating a New Skill
Use theinit command to create a skill template:
SKILL.md template with proper frontmatter structure.
Related Documentation
CLI Options
Learn how to install and manage skills
Agent Config
Understand agent-specific configurations
Contributing
Guidelines for creating and sharing skills
Agent Skills Spec
Official specification for agent skills