Rule catalog
93 rules across 15 categories. Thirteen categories need nothing but the fetched HTML and response headers. Two, links and images, make extra requests. Accessibility and the Core Web Vitals half of performance need a rendered page.
Every rule id is category/name, and the category half is what only and skip accept.
Core SEO
10 rules. The checks a search engine reads first.
Performance
12 rules. The first six read the response. The last six need a rendered page and are skipped without one.
Security
12 rules, all read from response headers.
Structured data
11 rules covering JSON-LD parsing, types, and the two schemas that matter most.
URL structure
8 rules, applied to every crawled URL.
Content
6 rules on the page text and its heading structure.
Crawlability
6 rules. robots.txt and the sitemap are fetched once per site and shared.
Images
6 rules, read from every <img> on the page.
Links
5 rules. This category makes extra requests: every unique link is checked once and the result is cached for the whole run.
Social media
4 rules on the sharing metadata.
Legal
4 rules looking for the pages a compliant site is expected to carry.
E-E-A-T
4 rules on experience, expertise, authority, and trust signals.
Analytics
2 rules.
Internationalization
2 rules on hreflang.
Accessibility
1 rule that emits many findings. The full axe-core WCAG pass runs against the rendered page and each violation becomes its own finding, carrying its own axe rule id, impact, and help URL.
Without browser: true or a psiKey, this rule is skipped rather than failed.