creating-skills

Structure SKILL.md with YAML frontmatter containing required fields, followed by clear instructions and task descriptions. Claude invokes Skills when the description precisely matches the user's intent, so craft descriptions that articulate the exact problem solved and when to use it.

Write descriptions that explicitly name the problem solved and the conditions triggering the Skill. Include concrete task verbs, expected inputs, and outputs. Avoid generic language; be specific about the specialized task your Skill handles so Claude recognizes the exact moment to invoke it.

Use progressive disclosure: keep SKILL.md focused on core instructions and YAML frontmatter, while reference.md contains detailed schemas, examples, and advanced patterns. This prevents information overload and ensures Claude receives the right details at the right time during execution.

Required YAML frontmatter fields depend on your Skill's scope, but must include metadata that helps Claude identify and validate the Skill's purpose. Refer to the Skill Unit format and validation rules for the complete set; optional fields include tool-restriction schemas for scoped execution.

Yes. Progressive disclosure splits instruction logic across SKILL.md for immediate tasks and reference.md for advanced details, reducing cognitive load on Claude. This pattern lets you design powerful, modular Skills without overwhelming the agent during autonomous invocation.

Custom Skills extend Claude's capabilities for specialized, repetitive tasks while maintaining context isolation and reusability. Modular Skills save time by enabling autonomous execution of domain-specific workflows without manual intervention or repeated prompt engineering.