web-design-guidelines
Vercel Labs' official skill, reviewing your interface code against the Web Interface Guidelines, the public reference the same team maintains in a separate repository. Its one distinguishing trait: it embeds no frozen copy of the rules, it fetches the current reference file on every run, so it does not age between install day and audit day. Findings come back in file:line form, usable straight from the editor. It ships inside a collection of Vercel skills installable in one command, MIT licensed. **Watch what it actually reads.** The skill does not fetch the public page [vercel.com/design/guidelines](https://vercel.com/design/guidelines) but its condensed version, the repository's `command.md` file. The qualitative rules are there (a visible focus and keyboard handling on every interactive element, never block paste in a field, keep the submit button enabled until the request starts, do not disable zoom, avoid `autoFocus` on mobile), but the numeric thresholds are not: a hit target of at least 24 px, 44 px on mobile, and a 16 px minimum input font on mobile so iOS Safari does not zoom on focus. Also missing: the rule that a loading button keeps its original label. And neither version sets a contrast ratio: the full page only recommends measuring it with APCA rather than WCAG 2. Those are exactly the ones a demo shows off, like [Henri, ExplorIA](https://www.instagram.com/reel/DdzfOd_Dd9h/)'s, which flags “touch target too small” and “font too small” on the first pass, next to a “contrast 3.1:1” that no published rule puts a number on. If you want those findings, hand the agent the full page on top of the skill.
Strengths
- Rules are fetched on every run, so an old install never audits against a stale reference
- The reference is public and separate from the skill, so you can read it, cite it and argue with it
- Findings in file:line form, usable in your editor without translation
- Vercel's own MIT-licensed skill, installable in one command along with the rest of the collection
Limitations
- Depends on a remote repository at every run, so offline, or when the file moves, the audit shifts under you
- It checks against a general reference and knows nothing about your in-house design system
- Two audits months apart are not comparable, because the rule base may have moved
- The file it fetches is the condensed version: the pixel thresholds from the full page (24 and 44 px targets, 16 px mobile inputs) are not in it
Best for
- Defending a review finding to a team by pointing at the published rule rather than at your own opinion
- An accessibility and usability pass before shipping, on a front end with no established design system
- A non-technical profile who wants to read the findings and check the cited rule for themselves