By name: aigent-validator description: >- Validates AI agent skill definitions (SKILL.md files) against the Anthropic agent skill specification. Checks frontmatter fields (name, description), format rules, and body guidelines. Use when validating skills, checking SKILL.md files, or reviewing skill definitions for spec compliance. allowed-tools: Bash(aigent validate *), Bash(command -v *), Read, Glob argument-hint: "[skill-directory-or-file]"
Skill Validator
Setup
Check if aigent is available:
command -v aigent
With aigent CLI
If aigent is on $PATH, use the CLI for authoritative validation:
aigent validate <skill-directory>
Exit code 0 means valid. Non-zero means errors. Warnings are printed but do not cause failure.
If a SKILL.md file path is provided instead of a directory, aigent
automatically resolves to the parent directory.
Without aigent CLI
If aigent is not available, validate manually by reading the SKILL.md
and checking these rules:
Frontmatter checks
- File starts and ends with
---delimiters namefield: present, string, ≤ 64 chars, lowercase + hyphens + numbers only, no consecutive hyphens, no leading/trailing hyphens, no reserved words ("anthropic", "claude"), no XML tags, matches directory namedescriptionfield: present, string, non-empty, ≤ 1024 chars, no XML tags
Optional field checks
compatibility: if present, string, ≤ 500 charslicense: if present, stringallowed-tools: if present, string
Body checks
- Body ≤ 500 lines (warning, not error)
Report format
Report each issue on its own line. Prefix warnings with "warning: ".