数据库 MCP（PostgreSQL / MySQL / Redis）

Use when reviewing scripts, client components, bundles, or runtime behavior related to Prefer const and let over var. 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 Remove console statements in production. Inspect both source code and the browser execution path so fixes target the real bottleneck or bug.

Use when reviewing templates, rendered HTML, or shared components related to Remove comments and debug code in production. Validate the final browser-facing markup, not just the source framework abstraction.

Use when reviewing templates, rendered HTML, or shared components related to Make carousels accessible. Validate the final browser-facing markup, not just the source framework abstraction.

Use when reviewing scripts, client components, bundles, or runtime behavior related to Never use eval() or unsafe dynamic code execution. Inspect both source code and the browser execution path so fixes target the real bottleneck or bug.

Use when reviewing templates, rendered HTML, or shared components related to Make accordions keyboard navigable. Validate the final browser-facing markup, not just the source framework abstraction.

Use when reviewing templates, rendered HTML, or shared components related to Create accessible tooltips. Validate the final browser-facing markup, not just the source framework abstraction.

Use when reviewing templates, rendered HTML, or shared components related to Make notifications accessible. Validate the final browser-facing markup, not just the source framework abstraction.

Use when reviewing templates, rendered HTML, or shared components related to Create a custom 404 error page. Validate the final browser-facing markup, not just the source framework abstraction.

Use when reviewing navigation performance, browser lifecycle events, or resume-from-memory behavior. Check the actual browser lifecycle and restore path, not only static code patterns.

Use when reviewing CI coverage, automated checks, or test strategy related to Test across all major browsers. Focus on whether the rule is continuously verified, not just documented.

Use when applies to all interactive elements on touchscreen interfaces: buttons, links, checkboxes, radio buttons, form inputs, icon buttons, and menu items. Check CSS for min-width, min-height, width, height, and padding on interactive elements. Particularly important for icon-only buttons (close, delete, share) which are often made too small.

Use when applies to hyperlinks (`<a>` elements) that appear inline within paragraphs or text blocks. Does not apply to navigation menus, button-style links, or standalone links that are visually isolated from body text. Use when reviewing CSS that removes text-decoration from inline body copy links.

Use when reviewing stylesheets, component styles, and responsive behavior related to Lint CSS and SCSS files. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when reviewing stylesheets, component styles, and responsive behavior related to Keep CSS specificity low and flat. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when reviewing article images, cards, galleries, or any component rendered at multiple sizes across breakpoints. Check both the markup and the CSS layout because an incorrect `sizes` attribute can negate a perfectly good `srcset`.

Use when reviewing stylesheets, component styles, and responsive behavior related to Use consistent CSS naming conventions. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when auditing server configuration or diagnosing broken resources. Applies to any web server serving HTML, CSS, JS, images, fonts, or other static assets.

Use when reviewing stylesheets, component styles, and responsive behavior related to Use CSS logical properties for i18n and RTL support. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when applies to HTML documents with `<li>` elements. Also applies to custom ARIA lists where `role='listitem'` must be owned by `role='list'`. Common violations occur in templating systems where list markup is split across components or in CSS resets where developers use `<li>` for layout without proper list parents.

Use when applies to all CSS layout rules. Check `width`, `min-width`, fixed pixel values on containers, `overflow`, `white-space`, and `word-break` properties. Use when auditing responsive design or WCAG 2.1 Level AA compliance. Test at 320px viewport width and at 400% browser zoom.

Use when reviewing CSS for fixed dimensions, truncation, or overflow rules on elements that render translatable strings.

Use when applies to CSS and JavaScript implementations of modals, overlays, pop-ups, cookie banners, newsletter sign-up dialogs, and promotional overlays. Check for `position: fixed`, `position: absolute` with large z-index, backdrop overlays, and JavaScript that shows modals on page load or shortly after. Consider both SEO impact (Google) and accessibility (WCAG focus management).

Use when reviewing a CSS architecture for specificity issues, setting up a design system, or migrating a large codebase from utility-first to a layered architecture.

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 stylesheets, component styles, and responsive behavior related to Support dark mode with prefers-color-scheme. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when reviewing rendered HTML, layout components, or design-system patterns that may depend on presentation for meaning. Check the DOM order, semantic structure, form relationships, and whether CSS generated content carries essential information.

Use when reviewing stylesheets, component styles, and responsive behavior related to Remove unused CSS rules. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when reviewing stylesheets, component styles, and responsive behavior related to Use a CSS reset or normalize stylesheet. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when applies to any `<meta name='viewport'>` element in HTML documents. Check the `content` attribute for `user-scalable=no`, `user-scalable=0`, `maximum-scale=1`, or `maximum-scale` values less than 2. This is a common mistake in mobile-first templates and CSS frameworks.

Use when applies to all CSS `font-size` declarations, particularly those using `px` units for body text, UI labels, and navigation. Use when auditing mobile responsiveness and accessibility compliance. Check for `font-size` in media queries targeting small screens.

Use when reviewing mobile-first layouts, tablet experiences, fullscreen flows, forms, dashboards, or media interfaces. Check rendered behavior in both portrait and landscape and separate genuine layout constraints from unnecessary orientation assumptions.

Use when setting up integration testing for a frontend-backend API boundary, evaluating whether two services are safe to deploy independently, or replacing slow end-to-end tests with contract tests.

Use when auditing tsconfig.json for missing safety flags, reviewing code that uses array index access in data processing pipelines, or investigating runtime undefined errors that TypeScript did not catch.

Use when auditing import statements in TypeScript files, setting up a new TypeScript project, or investigating unexpected bundle inclusions from type-only dependencies.

Use when reviewing TypeScript files for type safety regressions, during code review of functions that handle external data, or when the codebase has ESLint warnings for @typescript-eslint/no-explicit-any.

Use when applies to all HTML documents. Always check the very first line of the raw HTML source (view-source: or DevTools > Network > Response). In SSR frameworks, check the root HTML template (e.g., _document.tsx in Next.js, index.html in Vite/Vue, application.html.erb in Rails). The doctype is not a tag — it is a declaration and does not need a closing tag.

Use when reviewing server-side rendering setup, Next.js App Router pages, or Node.js HTTP handlers to verify that HTML is streamed incrementally rather than buffered until completion.

Use when reviewing large SPA bundles, new dependency additions, or routes that feel slow to hydrate. Focus on code that is not required for the initial view and can move behind route transitions, user interaction, or viewport-based loading.

Use when auditing slow page loads, heavy assets, or rendering delays related to Enable browser caching. Verify the actual bottleneck in DevTools, Lighthouse, or field data before recommending changes.

Use when auditing slow page loads, heavy assets, or rendering delays related to Perform browser-based performance audits. Verify the actual bottleneck in DevTools, Lighthouse, or field data before recommending changes.

Use when applies to product pages, local business pages, recipes, apps, books, and any page that aggregates user reviews. Use when auditing rich result eligibility for e-commerce or review sites.

Use when reviewing stylesheets, component styles, and responsive behavior related to Inline critical CSS for faster rendering. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when reviewing stylesheets, component styles, and responsive behavior related to Order CSS files correctly. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when reviewing stylesheets, component styles, and responsive behavior related to Minify all CSS files. Check the rendered layout across breakpoints and interaction states before proposing a fix.

Use when reviewing stylesheets, component styles, and responsive behavior related to Load CSS without blocking render. Check the rendered layout across breakpoints and interaction states before proposing a fix.