web-design-guidelines
UI/UX best practices and accessibility audit. Use when reviewing UI code, checking accessibility, running accessibility audits, auditing forms, or ensuring web interface best practices. Triggers on "audit accessibility", "check WCAG", "review UI", "check accessibility", "audit de
What it does
Web Design Guidelines
WCAG accessibility, semantic HTML, keyboard navigation, forms, and performance patterns for inclusive web interfaces. Contains 23 rules across 4 categories. Supports both coding reference and audit mode.
Metadata
- Version: 2.1.0
- Rule Count: 23 rules across 4 categories
- License: MIT
How to Audit
When the user asks to "audit accessibility", "check WCAG compliance", or "review accessibility" — run the checklist below against their codebase.
Step 1: Determine Scope
- If arguments provided (
$ARGUMENTS): audit only those files or components - If no arguments: audit all UI components and pages in the codebase
Step 2: Detect Stack
Check the project for:
.tsx/.jsxfiles → React.vuefiles → Vue.blade.phpfiles → Laravel Blade.htmlfiles → Static HTML
Step 3: Run Accessibility Checklist
Work through every item below. For each, output:
- PASS — brief confirmation of what was verified
- FAIL — exact
file:line, description of the issue, and fix recommendation - N/A — if the check does not apply to this project
Semantic HTML & Structure
- Pages use semantic elements (
<header>,<main>,<nav>,<footer>,<article>,<section>) — not<div>soup - Heading hierarchy is sequential (
h1→h2→h3) — no skipped levels - One
<h1>per page - Skip link exists to bypass navigation (
<a href="#main-content">Skip to content</a>) - Landmark regions are labelled when duplicated (
aria-labelon multiple<nav>elements)
Keyboard Navigation
- All interactive elements are reachable via Tab key
- Focus order follows visual order (no positive
tabindexvalues) - Focus indicator is visible on all focusable elements (not removed with
outline: nonewithout replacement) - Modal dialogs trap focus and return focus on close
- Custom components (dropdowns, tabs, accordions) support expected keyboard patterns (Arrow keys, Escape, Enter)
Images & Media
- All
<img>elements havealtattributes — descriptive for content images, empty (alt="") for decorative - Complex images (charts, diagrams) have extended descriptions
- Video content has captions or transcripts
Color & Contrast
- Text meets WCAG AA contrast ratio (4.5:1 for normal text, 3:1 for large text)
- Information is not conveyed by color alone (e.g., error states use icons + text, not just red)
- UI components and focus indicators meet 3:1 contrast ratio against background
Forms
- Every input has an associated
<label>(not just placeholder text) - Required fields indicated with both visual cue and
aria-required="true" - Error messages linked to inputs via
aria-describedby - Error messages use
role="alert"oraria-live="assertive"for screen reader announcement - Correct
typeattributes on inputs (email,tel,url,number) -
autocompleteattributes present on common fields (name, email, address, credit card)
ARIA & Screen Readers
- ARIA labels on icon-only buttons (
aria-label="Close") - Dynamic content updates use
aria-liveregions - Loading states announced to screen readers (
aria-busy="true", status messages) - Decorative elements hidden from screen readers (
aria-hidden="true")
Motion & Animation
-
prefers-reduced-motionrespected — animations disabled or reduced - No auto-playing video or audio without user control
- No content that flashes more than 3 times per second
Step 4: Summary
End the audit with:
## Accessibility Audit Summary
- **PASS**: X checks
- **FAIL**: X checks
- **N/A**: X checks
- **WCAG Level**: AA / Partial AA / Below AA
- **Top Priority Fixes**: (list the 3 most impactful FAIL items)
When to Apply
Reference these guidelines when:
- Running an accessibility audit on a codebase
- Reviewing UI code for accessibility (WCAG compliance)
- Implementing forms and interactions
- Ensuring keyboard navigation works
- Adding ARIA labels and live regions
- Optimizing image loading and layout stability
Rule Categories by Priority
| Priority | Category | Impact | Prefix |
|---|---|---|---|
| 1 | Accessibility | CRITICAL | a11y- |
| 2 | Forms | HIGH | form- |
| 3 | Animation & Motion | CRITICAL | motion- |
| 4 | Performance & UX | MEDIUM | perf- |
Quick Reference
1. Accessibility (CRITICAL)
a11y-semantic-html- Use semantic HTML elementsa11y-heading-hierarchy- Maintain proper heading hierarchya11y-screen-reader- Optimize for screen reader compatibilitya11y-skip-links- Provide skip links for navigationa11y-keyboard-nav- Ensure full keyboard navigationa11y-focus-management- Manage keyboard focus properlya11y-aria-labels- Add ARIA labels to interactive elementsa11y-color-contrast- Ensure sufficient color contrast (WCAG AA)a11y-alt-text- Provide meaningful alt text for imagesa11y-error-messages- Make error messages accessiblea11y-form-labels- Associate labels with form inputsa11y-live-regions- Announce dynamic content to screen readers
2. Forms (HIGH)
form-autocomplete- Use autocomplete attributesform-input-types- Use correct input typesform-error-display- Display form errors clearlyform-validation-ux- Design user-friendly validationform-inline-validation- Implement smart inline validationform-multi-step- Design effective multi-step formsform-placeholder-usage- Use placeholders appropriatelyform-submit-feedback- Provide clear submission feedback
3. Animation & Motion (CRITICAL)
motion-reduced- Respect prefers-reduced-motion (WCAG AAA)
4. Performance & UX (MEDIUM)
perf-image-loading- Optimize image loading for UXperf-layout-stability- Prevent cumulative layout shift
Essential Guidelines
Semantic HTML
// ❌ Div soup
<div className="header"><div className="nav"><div onClick={handleClick}>Home</div></div></div>
// ✅ Semantic HTML
<header><nav aria-label="Main"><a href="/">Home</a></nav></header>
<main><article><h1>Title</h1><p>Content</p></article></main>
Form Accessibility
<label htmlFor="email">Email <span aria-hidden="true">*</span></label>
<input id="email" type="email" required aria-required="true" aria-describedby="email-error" autoComplete="email" />
{error && <p id="email-error" role="alert">{error}</p>}
Reduced Motion
@media (prefers-reduced-motion: reduce) {
*, *::before, *::after {
animation-duration: 0.01ms !important;
transition-duration: 0.01ms !important;
}
}
How to Use
Read individual rule files for detailed explanations:
rules/a11y-semantic-html.md
rules/form-autocomplete.md
rules/motion-reduced.md
rules/perf-image-loading.md
References
- WCAG 2.2 Quick Reference
- WAI-ARIA Authoring Practices
- web.dev Accessibility
- MDN Accessibility
- The A11Y Project
Full Compiled Document
For the complete guide with all rules expanded: AGENTS.md
Capabilities
Install
Quality
deterministic score 0.47 from registry signals: · indexed on github topic:agent-skills · 39 github stars · SKILL.md body (7,336 chars)