Free Tool · No account · Instant
SKILL.md Linter
Paste your SKILL.md file. Get a scored quality report across 8 dimensions — frontmatter, description, trigger, output format, examples, iron laws, token budget, error handling. 100% algorithmic. No CLI needed.
Something went wrong.
Detected Frontmatter Fields
8 Dimensions scored
1 · 20 pts
Frontmatter Completeness
Required fields: name (or skill), description, trigger (or when/argument-hint). Optional: version, modes, author, model, context.
2 · 15 pts
Description Quality
50–300 chars is ideal. Must describe what it does and when. Vague ("does tasks") or overlong descriptions penalized.
3 · 15 pts
Trigger Clarity
Trigger should specify the exact phrase or condition that activates the skill. "When the user asks to X" format is gold standard.
4 · 15 pts
Output Format
Output Format or Response Format section present. Specifies structure: JSON, markdown, plain text. Examples in the section are a bonus.
5 · 12 pts
Iron Laws / Constraints
Iron Laws, Constraints, or Rules section present. At least 3 constraints listed. Explicit "never" or "always" rules score higher.
6 · 10 pts
Examples
At least one concrete example (input/output pair, usage sample, or worked example). Examples dramatically improve agent adherence.
7 · 8 pts
Token Budget
Under 800 tokens: optimal. 800–2000: good. 2000–8000: acceptable. Over 8000: too long — agents hit saturation and skip sections.
8 · 5 pts
Error Handling
Error recovery, edge cases, or failure modes section present. What should the agent do when the input is ambiguous or the task fails?