Agent Skill Validator

Validate your Agent Skill

Check the compliance of SKILL.md with skills specification & skills-ref rules

Input

Paste your SKILL.md (frontmatter + body). Use Ctrl+Enter to validate.

Paste your SKILL.md above.

What this validator checks

Files validated

  • SKILL.md — The standard filename for Cursor Agent Skills (frontmatter + markdown body)

Specifications & compliance

This tool validates against the Agent Skills specification and skills-ref rules.

Compliance rules

  • YAML frontmatter — Must start and end with ---; valid YAML mapping only
  • Allowed fields — Only name, description, license, allowed-tools, metadata, compatibility
  • name — Required; lowercase; letters, digits, hyphens only; no leading/trailing or consecutive hyphens; max 64 characters
  • description — Required; max 1024 characters; 50+ characters recommended
  • compatibility — Optional; must be string if present; max 500 characters
  • metadata — Optional; key-value map (e.g. author, version)
  • license — Optional (e.g. MIT, Apache-2.0)
  • Body — Markdown instructions; ~500 non-empty lines recommended; empty body triggers a warning

How to use the Agent Skill Validator

Steps

  1. Paste your SKILL.md content (frontmatter and body) into the input.
  2. Click Validate or press Ctrl+Enter (Cmd+Enter on Mac).
  3. Review errors, warnings, and suggestions; fix your file and re-validate as needed.
  4. Use Load sample to see an example that passes validation.

Terms

Frontmatter

YAML between the first --- and the closing ---. Must include name and description; other fields are optional.

Name

Lowercase, letters/digits/hyphens only; no leading/trailing hyphens or consecutive hyphens. Max 64 characters.

Description

Short summary of what the skill does and when to use it. Max 1024 characters; 50+ characters recommended.

Frequently Asked Questions