Use when auditing slow page loads, heavy assets, or rendering delays related to Remove duplicate JavaScript libraries. Verify the actual bottleneck in DevTools, Lighthouse, or field data before recommending changes.
Use when reviewing CI coverage, automated checks, or test strategy related to Implement end-to-end testing. Focus on whether the rule is continuously verified, not just documented.
Use when auditing a blog, news site, or YMYL content site for trust signals, drafting editorial policy page content, or evaluating whether a site meets Google's quality rater trustworthiness criteria.
Use when reviewing stylesheets, component styles, and responsive behavior related to Avoid embedded and inline CSS. Check the rendered layout across breakpoints and interaction states before proposing a fix.
Use when reviewing rendered HTML, interactive components, or design-system patterns related to Ensure headings contain text. Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output where relevant.
Use when reviewing rendered HTML, interactive components, or design-system patterns related to Fix empty and broken links. Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output where relevant.
Use when reviewing scripts, client components, bundles, or runtime behavior related to Implement proper error handling. Inspect both source code and the browser execution path so fixes target the real bottleneck or bug.
Use when reviewing image assets, markup, and CDN or build transforms related to Handle image loading errors gracefully. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.
Use when setting up a new project's production observability stack, reviewing incident response readiness, or investigating why errors are going undetected.
Use when reviewing scripts, client components, bundles, or runtime behavior related to Use ES modules (import/export). Inspect both source code and the browser execution path so fixes target the real bottleneck or bug.
Use when reviewing scripts, client components, bundles, or runtime behavior related to Use event delegation for dynamic content. Inspect both source code and the browser execution path so fixes target the real bottleneck or bug.
Use when auditing content pages for citation quality, suggesting authoritative sources to link for factual claims, or reviewing whether a page's external link attributes (nofollow, noopener) are correctly set.
Use when adding FAQ sections to landing pages or blog posts, generating FAQPage JSON-LD from existing Q&A content, or validating that structured data on pages with FAQ sections is syntactically and semantically correct.
Use when reviewing templates, rendered HTML, or shared components related to Implement favicons for all devices. Validate the final browser-facing markup, not just the source framework abstraction.
Use when optimising Largest Contentful Paint (LCP), reducing render-blocking resource contention, or fine-tuning resource loading order in the critical rendering path.
Use when reviewing image assets, markup, and CDN or build transforms related to Use and for image captions. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.
Use when reviewing templates, rendered HTML, or shared components related to Make file uploads accessible. Validate the final browser-facing markup, not just the source framework abstraction.
Use when reviewing image assets, markup, and CDN or build transforms related to Use descriptive image filenames. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.
Use when you need to find the 2-3 most popular and well-maintained npm packages relevant to a frontend checklist rule, validate they meet quality thresholds, and add them to the rule's frontmatter.
Use when auditing slow page loads, heavy assets, or rendering delays related to Optimize first contentful paint. Verify the actual bottleneck in DevTools, Lighthouse, or field data before recommending changes.
Use when reviewing rendered HTML, interactive components, or design-system patterns related to Prevent seizure-triggering flashing content. Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output where relevant.
Use when reviewing stylesheets, component styles, and responsive behavior related to Apply Flexbox best practices. Check the rendered layout across breakpoints and interaction states before proposing a fix.
At most 3 mods per repository are shown here, and a mod shipped inside a plugin is left to that plugin's page β the rest are on their repository pages: