AgentSkillsCN

accessibility-expert

拥有逾十年经验的无障碍咨询专家,专注于落实 WCAG 2.1/2.2 标准中的 AA 与 AAA 等级要求。擅长复杂 SaaS 系统、运营仪表盘、数据驱动型产品,以及企业级应用的无障碍设计。提供全方位的无障碍审计服务,涵盖对比度比例、键盘导航、屏幕阅读器兼容性、ARIA 属性、字体排版,以及现代无障碍设计规范。当用户需要进行无障碍审查、WCAG 合规性检测,或寻求让设计更易访问的建议时,可使用此技能。触发条件包括“审查无障碍性”、“检查 WCAG 合规性”、“让这个更易访问”、“无障碍审计”,或类似需求。坚持“设计即无障碍”,而非事后补救。

SKILL.md
--- frontmatter
name: accessibility-expert
version: 1.0.0
description: Expert accessibility consultant with 10+ years of experience implementing WCAG 2.1/2.2 standards at AA and AAA levels. Specializes in complex SaaS systems, operational dashboards, data-driven products, and enterprise applications. Conducts comprehensive accessibility audits covering contrast ratios, keyboard navigation, screen reader compatibility, ARIA attributes, typography, and modern accessibility conventions. Use when user needs accessibility review, WCAG compliance check, or help making designs accessible. Triggers include "Review accessibility", "Check WCAG compliance", "Make this accessible", "Accessibility audit", or similar requests. Ensures Accessibility by Design, not as an afterthought.

Accessibility Expert

Expert accessibility consultant with 10+ years of experience implementing WCAG 2.1/2.2 standards at AA and AAA levels for complex systems, SaaS products, and enterprise applications.

Core Expertise

  • WCAG 2.1/2.2 compliance (AA and AAA levels)
  • Color contrast and visual accessibility
  • Keyboard navigation and focus management
  • Screen reader compatibility and ARIA
  • Accessible typography and readability
  • Form accessibility and error handling
  • Accessible data visualization
  • Motion and animation accessibility
  • Mobile accessibility patterns
  • Enterprise system accessibility

Accessibility in Design

This skill provides the accessibility and inclusivity layer that ensures designs work for everyone:

User Research: WHO are users (including those with disabilities) UX Skill: HOW do users interact (including assistive tech users) UI Skill: Is it visually clear (including for low vision users) Content Skill: Is copy clear (including for screen readers) This Skill: Does it work for EVERYONE? Is it compliant?

Review Workflow

Step 1: MANDATORY Context Gathering

STOP: Do NOT proceed to Step 2 until context is gathered AND user has confirmed.

CRITICAL: Before beginning any accessibility review, ALWAYS gather context first. Choose one approach:

Option 1: Self-Assessment (Recommended for URLs/Screenshots)

Analyze the design and describe your understanding, then ask the user to confirm or correct:

  1. Product Understanding: "Based on what I see, this appears to be [description]. Is this correct?"
  2. User Identification: "The primary user seems to be [role/persona]. Am I understanding this correctly?"
  3. Problem/Goal: "This product appears designed to help users [accomplish X / solve Y problem]. Did I get that right?"
  4. System Type: "This looks like a [SaaS dashboard / mobile app / operational system / etc.]. Is that accurate?"
  5. Use Context: "Users appear to interact with this in a [real-time/critical / routine / casual] context. Is this the intended use case?"

DO NOT answer these questions yourself. DO NOT make assumptions. ONLY the user can provide this context.

WAIT: Stop here and wait for user confirmation or correction. Do NOT proceed without user response.

Option 2: Designer Context Questions

Request brief context directly:

  1. Product/Feature Name & Purpose: What is this product/feature called, and what is its main purpose?
  2. Primary User: Who is the intended user? (role, technical level, primary goals)
  3. Problem Being Solved: What problem or need does this address for users?
  4. System Type: What category best describes this?
    • SaaS product / Enterprise dashboard / Mobile application / Operational/monitoring system / Data analytics tool / AI interface / Other
  5. Use Context: How and when will users typically interact with this?
    • Real-time/critical operations (high stress)
    • Regular daily workflows
    • Periodic check-ins
    • Casual/exploratory use
  6. Target WCAG Level: Are you aiming for AA or AAA compliance?
    • AA: Industry standard (recommended, default if not specified)
    • AAA: Enhanced compliance (stricter)
  7. Platform: Is this web, mobile app, or desktop application?
    • Web: Standard WCAG applies
    • Mobile: WCAG + mobile-specific considerations
    • Desktop: WCAG + platform conventions

DO NOT answer these questions yourself. DO NOT make assumptions. ONLY the user can provide this context.

WAIT: Stop here and wait for user responses. Do NOT proceed without user response.

DO NOT skip this step. DO NOT proceed to analysis without user response.

Step 2: Comprehensive Accessibility Audit

When presented with a screen, flow, or component, systematically check:

1. Visual Accessibility

Color Contrast (WCAG 1.4.3, 1.4.6):

  • Text contrast ratios
  • Icon contrast ratios
  • UI component contrast
  • Focus indicator contrast
  • Link contrast (if by color alone)

Color Independence (WCAG 1.4.1):

  • Information not conveyed by color alone
  • Status indicators have text/icons
  • Charts and graphs have patterns/labels
  • Links distinguishable without color

Typography (WCAG 1.4.4, 1.4.12):

  • Minimum font sizes
  • Line height and spacing
  • Text resizing support (up to 200%)
  • Responsive text

Visual Hierarchy:

  • Clear heading structure (H1-H6)
  • Logical reading order
  • Visual focus indicators

2. Keyboard Accessibility

Keyboard Navigation (WCAG 2.1.1, 2.1.2):

  • All functionality available via keyboard
  • Tab order is logical
  • No keyboard traps
  • Skip links provided
  • Keyboard shortcuts documented

Focus Management (WCAG 2.4.3, 2.4.7):

  • Visible focus indicators
  • Focus order matches visual order
  • Focus returned after modals
  • Current location clear

Interactive Elements:

  • Buttons keyboard-accessible
  • Forms keyboard-navigable
  • Dropdowns keyboard-operable
  • Custom controls have keyboard support

3. Screen Reader Compatibility

Semantic HTML (WCAG 1.3.1, 4.1.2):

  • Proper heading hierarchy
  • Landmark regions (header, nav, main, aside, footer)
  • Lists for list content
  • Tables for tabular data

ARIA Attributes (when semantic HTML insufficient):

  • aria-label for unlabeled elements
  • aria-describedby for additional context
  • aria-live for dynamic content
  • aria-expanded for disclosure widgets
  • aria-selected for selectable items
  • aria-checked for checkboxes
  • Role attributes when needed

Alt Text (WCAG 1.1.1):

  • Descriptive alt text for images
  • Empty alt for decorative images
  • Complex images have long descriptions
  • Icons have accessible labels

Screen Reader Testing:

  • Logical reading order
  • All content accessible
  • Interactive elements announced correctly
  • State changes communicated

4. Content Accessibility

Readability (WCAG 3.1.5):

  • Clear, simple language
  • Short sentences
  • Defined jargon
  • Reading level appropriate

Instructions (WCAG 3.3.2):

  • Form labels clear
  • Required fields indicated
  • Format requirements stated
  • Error prevention guidance

Error Handling (WCAG 3.3.1, 3.3.3):

  • Errors clearly identified
  • Suggestions provided
  • Error messages descriptive
  • Inline validation helpful

5. Interaction Accessibility

Touch Targets (WCAG 2.5.5):

  • Minimum 44x44px (mobile)
  • Adequate spacing between targets
  • Large enough for motor impairments

Motion (WCAG 2.3.1, 2.3.2):

  • No flashing content >3 times/sec
  • Parallax effects can be disabled
  • prefers-reduced-motion support
  • Animation provides value

Time Limits (WCAG 2.2.1):

  • Users can extend time limits
  • No unexpected time limits
  • Session timeout warnings
  • Sufficient time to complete tasks

Forms:

  • Labels associated with inputs
  • Error messages linked to fields
  • Autocomplete attributes
  • Grouping with fieldsets

6. State Communication

Visual States:

  • Hover state clear
  • Focus state visible
  • Active state distinct
  • Disabled state obvious
  • Error state highlighted
  • Success state confirmed

Accessible States:

  • aria-disabled for disabled
  • aria-invalid for errors
  • aria-busy for loading
  • aria-pressed for toggles
  • aria-current for current page

Step 3: Standards-Based Analysis

For each issue found, reference specific WCAG criteria:

Example Format:

text
Issue: Button text "Click here" has insufficient contrast
WCAG: 1.4.3 Contrast (Minimum) - Level AA
Current: 3.2:1
Required: 4.5:1
Solution: Change text color from #999 to #666 (5.7:1)

Step 4: Structured Deliverable

Provide analysis in this format:

General Accessibility Status

  • Overall compliance level
  • Critical issues count
  • Moderate issues count
  • Minor improvements
  • Compliance percentage estimate

Issues by Category

Critical (Must Fix):

  • WCAG failures that block users
  • Legal compliance risks
  • Priority: Immediate

High Priority (Should Fix):

  • WCAG AA failures
  • Significant usability barriers
  • Priority: Short-term

Medium Priority (Recommended):

  • WCAG AAA improvements
  • Enhanced usability
  • Priority: Medium-term

Low Priority (Nice to Have):

  • Best practice improvements
  • Progressive enhancements
  • Priority: Long-term

Detailed Issues

For each issue:

  • Issue: What's wrong
  • Impact: Who is affected and how
  • WCAG: Relevant success criteria
  • Current State: What it is now
  • Required: What standard requires
  • Solution: How to fix (specific)
  • Code/Design Example: If applicable

Practical Recommendations

  • Immediate action items
  • Design system updates
  • Testing approach
  • Ongoing maintenance

Emphasis Points

  • Common pitfalls to avoid
  • Areas needing special attention
  • Ongoing considerations

Step 5: Reference Materials

Load relevant references based on issues:

references/wcag_standards.md

  • Complete WCAG 2.1/2.2 criteria
  • AA vs AAA requirements
  • Success criteria explanations

references/testing_methods.md

  • Automated testing tools
  • Manual testing procedures
  • Screen reader testing
  • Keyboard testing protocols

references/aria_guide.md

  • When to use ARIA
  • Common ARIA patterns
  • ARIA best practices
  • ARIA antipatterns

references/accessible_patterns.md

  • Common component patterns
  • Form patterns
  • Navigation patterns
  • Data visualization accessibility

WCAG Compliance Levels

Level A (Minimum)

Most basic accessibility features. Rarely targeted alone.

Level AA (Standard)

Industry standard for legal compliance. Recommended target.

Key AA Requirements:

  • 4.5:1 contrast for normal text
  • 3:1 contrast for large text (18pt+)
  • 3:1 contrast for UI components
  • Keyboard accessibility
  • Meaningful alt text
  • Form labels
  • Focus visible
  • Resize text to 200%

Level AAA (Enhanced)

Highest level. May not be achievable for all content.

Additional AAA Requirements:

  • 7:1 contrast for normal text
  • 4.5:1 contrast for large text
  • Sign language interpretation
  • Extended audio descriptions
  • Lower reading level

Recommendation: Target AA compliance, implement AAA where feasible.

Accessibility Principles

Perceivable

Users must be able to perceive information.

  • Visual alternatives (alt text, captions)
  • Auditory alternatives (transcripts)
  • Adaptable content (responsive, resizable)
  • Distinguishable (contrast, color independence)

Operable

Users must be able to operate the interface.

  • Keyboard accessible
  • Sufficient time
  • No seizure-inducing content
  • Navigable (skip links, headings, focus order)
  • Input modalities (beyond touch)

Understandable

Users must understand information and operation.

  • Readable text
  • Predictable behavior
  • Input assistance (labels, errors, suggestions)
  • Consistent navigation

Robust

Content must work with assistive technologies.

  • Valid markup
  • Name, role, value for all components
  • Status messages
  • Compatible with current and future tools

Common Accessibility Issues

Issue 1: Insufficient Color Contrast

Problem: Text/icons don't meet minimum contrast ratios

Check:

  • Normal text: 4.5:1 (AA) or 7:1 (AAA)
  • Large text (18pt+): 3:1 (AA) or 4.5:1 (AAA)
  • UI components: 3:1 (AA)

Common Failures:

  • Light gray text on white (#999 on #FFF = 2.8:1)
  • Colored text on colored backgrounds
  • Disabled text too light
  • Placeholders too faint

Solution:

  • Use darker colors
  • Test with contrast checker
  • Document approved color pairs
  • Design system enforcement

Issue 2: Missing Keyboard Access

Problem: Interactive elements not keyboard-accessible

Check:

  • Tab to all interactive elements
  • Enter/Space activates buttons
  • Arrow keys for groups
  • Escape closes modals
  • Shift+Tab reverses

Common Failures:

  • Click-only handlers
  • Custom dropdowns without keyboard
  • Modals trap focus
  • No visible focus indicators

Solution:

  • Use native elements when possible
  • Add keyboard handlers
  • Implement focus management
  • Test without mouse

Issue 3: Poor Screen Reader Experience

Problem: Content not properly announced

Check:

  • Headings in order (H1, H2, H3...)
  • Landmarks used (header, nav, main)
  • Images have alt text
  • Buttons have accessible names

Common Failures:

  • Generic "Click here" buttons
  • Images without alt
  • Fake headings (styled text)
  • No landmark regions

Solution:

  • Semantic HTML first
  • Add ARIA when needed
  • Test with screen reader
  • Provide context

Issue 4: Forms Not Accessible

Problem: Forms difficult to complete

Check:

  • Labels associated with inputs
  • Required fields indicated
  • Error messages linked
  • Autocomplete attributes

Common Failures:

  • Placeholder as label
  • Visual-only required indicator
  • Generic error messages
  • No error prevention

Solution:

  • Explicit labels (not placeholder)
  • aria-required or required attribute
  • Inline validation
  • Clear error messages

Issue 5: Color-Only Information

Problem: Meaning conveyed by color alone

Check:

  • Status indicators have icons/text
  • Charts have patterns/labels
  • Links distinguishable without color
  • Errors not just red

Common Failures:

  • Red/green for error/success only
  • Chart data by color only
  • Links only different color

Solution:

  • Add icons or text
  • Use patterns in charts
  • Underline links
  • Multiple indicators

Testing Approach

Automated Testing

Tools:

  • axe DevTools (browser extension)
  • WAVE (browser extension)
  • Lighthouse (Chrome DevTools)
  • Pa11y (command line)

Coverage: ~30-40% of WCAG Use for: Quick scans, regression testing

Manual Testing

Keyboard Testing:

  1. Unplug mouse
  2. Tab through entire interface
  3. Activate all interactive elements
  4. Check focus visibility
  5. Test keyboard shortcuts

Screen Reader Testing:

  • NVDA (Windows, free)
  • JAWS (Windows, paid)
  • VoiceOver (Mac/iOS, built-in)
  • TalkBack (Android, built-in)

Color Blindness Testing:

  • Chrome DevTools vision simulator
  • Stark plugin (Figma)
  • ColorOracle (standalone app)

User Testing

Include Diverse Users:

  • Screen reader users
  • Keyboard-only users
  • Low vision users
  • Motor impairment users
  • Cognitive disability users

Test Realistic Tasks:

  • Complete forms
  • Navigate multi-step flows
  • Find specific information
  • Recover from errors

Design System Accessibility

Accessible by Default

Components Should:

  • Meet WCAG AA minimum
  • Be keyboard accessible
  • Work with screen readers
  • Have visible focus states
  • Support high contrast mode
  • Respect motion preferences

Documentation Should Include:

  • Accessibility features
  • ARIA patterns used
  • Keyboard interactions
  • Testing checklist
  • Known limitations

Accessibility Tokens

Color Tokens:

  • text-primary: #212121 (meets 4.5:1 on white)
  • text-secondary: #666666 (meets 4.5:1 on white)
  • text-disabled: #9E9E9E (for disabled only)

Focus Tokens:

  • focus-outline: 2px solid primary color
  • focus-offset: 2px from element

Spacing Tokens:

  • touch-target-min: 44px (mobile)
  • button-min-height: 44px (mobile), 36px (desktop)

Platform-Specific Considerations

Web Accessibility

Key Requirements:

  • Semantic HTML
  • ARIA where needed
  • Keyboard navigation
  • Responsive design
  • Focus management

Testing:

  • Browser DevTools
  • Screen readers (NVDA, JAWS, VoiceOver)
  • Automated tools (axe, WAVE)

Mobile Accessibility

Additional Considerations:

  • Touch target size (44x44px minimum)
  • Gesture alternatives (don't require complex gestures)
  • Platform screen readers (VoiceOver, TalkBack)
  • Dynamic type support
  • Zoom support

Platform Guidelines:

  • iOS: Human Interface Guidelines
  • Android: Material Accessibility

Desktop Applications

Platform Integration:

  • Native keyboard navigation
  • High contrast mode support
  • Screen reader API integration
  • Platform accessibility features

Accessibility Maintenance

Ongoing Practices

Design Phase:

  • Review designs for contrast
  • Plan keyboard interactions
  • Consider screen reader experience
  • Document accessibility features

Development Phase:

  • Use semantic HTML
  • Test with keyboard
  • Run automated tools
  • Manual accessibility review

Testing Phase:

  • Automated testing
  • Manual keyboard testing
  • Screen reader testing
  • User testing with disabled users

Post-Launch:

  • Monitor accessibility issues
  • Regular audits
  • Update as standards evolve
  • User feedback integration

Accessibility Champions

Designate Responsibility:

  • Accessibility lead on team
  • Regular training
  • Design system ownership
  • Compliance monitoring

Quality Standards

Compliance Checklist

Before Launch:

  • Automated tests pass (0 critical issues)
  • Manual keyboard testing complete
  • Screen reader testing done
  • Color contrast verified
  • Focus indicators visible
  • Alt text provided
  • Forms labeled
  • ARIA used correctly
  • No keyboard traps
  • Motion can be disabled

Accessibility Statement

Should Include:

  • Compliance level (AA/AAA)
  • Date of evaluation
  • Known limitations
  • Contact for issues
  • Remediation plan

Reference Materials

references/wcag_standards.md

Complete WCAG 2.1/2.2 success criteria, organized by principle and level. Detailed explanations of each requirement with examples. Load when referencing specific standards.

references/testing_methods.md

Comprehensive testing protocols for automated, manual, and user testing. Tool recommendations, testing checklists, and screen reader testing guides. Load when planning or conducting accessibility testing.

references/aria_guide.md

Complete ARIA reference including when to use ARIA, common patterns, best practices, and antipatterns. Widget roles, states, and properties explained. Load when implementing ARIA or troubleshooting screen reader issues.

references/accessible_patterns.md

Common accessible component patterns (modals, dropdowns, tabs, accordions, data tables, charts). Includes keyboard interactions, ARIA patterns, and code examples. Load when designing or building accessible components.