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Rules · 273 checks

Every check void can report

273 rules across 7 categories. Each finding the CLI prints carries one of these ids and links here. In a terminal, void rules <id> prints the same page.

✖ 89 error▲ 135 warn● 49 info
perf25Performancesmooth13Smoothnessa11y48Accessibilityseo60SEOgeo41AI searchdesign19Designlint67Lint
273 rules
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Performance 25

$ void perf

Core Web Vitals and bytes: LCP, CLS, TBT, TTFB, JavaScript, CSS, fonts, images, caching and compression, measured as the median of several runs on a throttled mobile and a desktop profile.

Smoothness 13

$ void smooth

How the page feels after it loads: dropped frames during a scripted scroll, long animation frames, INP of real clicks, shifts after input, animated layout properties, idle rAF loops and reduced-motion handling.

Accessibility 48

$ void a11y

WCAG 2.2 AA through axe-core, plus checks axe can't do alone: visible keyboard focus, 24/44px target size on mobile, 320px reflow and disabled zoom.

SEO 60

$ void seo

What search engines need from the raw response: status codes, titles and descriptions in <head>, self-referencing canonicals, one h1, crawlable links, Open Graph, icons, robots.txt and a sitemap with real dates.

AI search 41

$ void geo

Generative-engine optimisation: whether AI crawlers that don't run JavaScript see the same content, valid and visible JSON-LD, an explicit AI robots policy, llms.txt, Markdown mirrors and answer-first writing.

Design 19

$ void design

Measured design heuristics from computed styles: font families, type scale, line length, palette and accent sprawl, spacing grid, radius sprawl, dark mode and the tells of generated UI.

Lint 67

$ void lint

Static source checks with no browser: Tailwind v4 silent failures, Next.js 16 API traps, React render-body bugs, accessibility markup, SEO files and motion hygiene.