A README badge with an agent skill's audit grade
Every agent skill and agent markdown file the registry has collected has a badge that shows its latest version and the grade the registry's automatic checks gave that version, from A to F. Paste one line of markdown into a README and the badge links to the file's page, where each check it passed or failed is listed.
Add it to a README
Find the file in the registry and open its page. Under Badge is the markdown to copy. For anthropics/skills/pdf it is:
[](https://markdownregistry.com/a/art_ce4b5ce6jbirfqqt)
The left side reads mdr. The right side shows the latest version the registry has recorded, by its version label, and that version's audit grade, so no one has to edit the README when a new version is graded. The grade belongs to that exact version, stored by the hash of its content. The registry lets the image be cached for five minutes, and a site that proxies README images, as GitHub does, can show an older copy for longer. A link to a file the registry does not hold shows a badge that reads unindexed.
What the grades mean
The grade comes from the same fixed checks for every file, with no model involved, so the same content gets the same grade under the same checks. A critical check is one such as a hidden zero-width or bidirectional control character; an advisory one is a pattern worth a look, such as curl or wget piped into a shell, or, for a skill, a missing frontmatter block. A grade is a pattern match, not a verdict on the author: read the checks on the file's page before you rely on it. To grade a file the registry does not hold, paste its GitHub link into the file check.
| Grade | What it means | Files | Share |
|---|---|---|---|
| A | Passes every check | 63,801 | 92.3% |
| B | Fails one advisory check | 4,061 | 5.9% |
| C | Fails two or more advisory checks | 1,063 | 1.5% |
| F | Fails a critical check | 194 | 0.3% |
What a badge records
Each time the image is fetched, the registry adds one to that file's count for the day and, when the request names the page it came from, records only that page's hostname, never the full address, as the privacy policy says. A site that fetches images through a proxy, as GitHub does for READMEs, may name no page at all, and one fetch there can serve many readers. A file's page shows its badge image fetches in the last 30 days.
Updated . How the checks work is on the about page, and what they find across the registry is in what to check before you install a skill.