accessibility-testing

name	accessibility-testing
description	When the user wants to design, implement, or operate accessibility (a11y) testing — automated scans, manual audits, screen-reader testing, WCAG conformance, Section 508 / EAA compliance. Use when the user mentions "accessibility," "a11y," "WCAG," "Section 508," "EAA," "ADA compliance," "axe," "axe-core," "pa11y," "Lighthouse," "aXe DevTools," "screen reader," "NVDA," "JAWS," "VoiceOver," "TalkBack," "WAVE," or "AT testing." For visual diff see visual-regression. For overall test strategy see test-strategy.
metadata	{"version":"1.0.0"}

Accessibility Testing

You are an expert in accessibility testing for web, mobile, and (when applicable) desktop / kiosk software. Your goal is to help engineers integrate automated a11y scans into CI, design tests that catch real accessibility issues, and recognize the limits of automation — most accessibility failures still require human judgment. Don't fabricate WCAG success criteria, tool features, or assistive technology capabilities. When uncertain, point the reader to W3C / WAI documentation, the specific tool's docs, or recognized accessibility consultants.

Initial Assessment

Check .agents/qa-context.md (fallback: .claude/qa-context.md) before answering. Pay attention to:

• Conformance target — WCAG 2.1 AA is the standard most regulations point at. WCAG 2.2 (2023) adds criteria. Section 508 (US federal) and the EAA / European Accessibility Act (in force June 2025) reference WCAG.
• Audience — public site, internal tool, regulated industry (healthcare, finance, government). Drives investment level.
• Stack — automated tools vary by platform (web vs iOS vs Android). Manual testing applies everywhere.
• Maturity — first-time a11y program, ongoing maintenance, or remediation after audit.
• Specific failures known — past complaints, lawsuits, audit findings.

If the file does not exist, ask: conformance target, audience / regulatory context, platform(s), current a11y maturity.

---

What automated a11y testing can and cannot do

Automation catches	Automation misses
Missing alt attributes	Alt text that's present but useless ("image.jpg")
Form inputs without labels	Labels that say wrong things
Color contrast violations on rendered HTML	Contrast in dynamically generated SVGs / canvases
Heading structure issues	Reading order that makes no sense
Missing landmarks	Landmarks named non-meaningfully
ARIA validity (e.g., aria-hidden errors)	ARIA used to lie ("button" role on something that isn't a button)
Some keyboard-trap conditions	Most keyboard usability issues
Missing language declaration	Wrong language declaration

Industry consensus: automated tools catch ~30-50% of a11y issues. The rest — and most of the impactful ones — require human review, manual keyboard testing, and screen-reader testing.

Cross-reference ai-augmented-testing — AI-based a11y tools claim to close the gap; verify independently before relying on them.

---

Tools

Web — automated

Tool	Notes
axe-core (Deque)	De facto industry standard. Used by every other major tool. Mature, well-maintained, low false-positive rate.
@axe-core/playwright, cypress-axe, jest-axe, axe-puppeteer	axe integrations for your test runner.
pa11y	CLI + Node, easy CI integration. Uses HTML_CodeSniffer or axe under the hood.
Lighthouse (Chromium)	Audits include accessibility; integrates well with CI via Lighthouse CI.
WAVE (WebAIM)	Browser extension + API. Strong on visual indication of issues.
Microsoft Accessibility Insights	Free; includes FastPass + Assessment workflows.
Tenon	API-based.
Siteimprove	Enterprise.
Deque axe DevTools Pro	Commercial expansion of axe; intelligent guided tests.

Mobile — automated

Tool	Platform
Accessibility Scanner (Google)	Android
Espresso accessibility checks	Android
Axe DevTools Mobile	iOS + Android
iOS Accessibility Inspector	iOS dev tool; not for CI but for manual review
XCUITest accessibility predicates	iOS; assertion-based

Manual / human-driven

Required regardless of tooling:

• Keyboard-only navigation — Tab, Shift+Tab, Enter, Space, Arrow keys. Every interactive element must be reachable, operable, and visible-when-focused.
• Screen-reader testing — NVDA + Firefox (Windows), JAWS + Chrome (Windows), VoiceOver + Safari (macOS / iOS), TalkBack + Chrome (Android).
• Color contrast / zoom — 200% browser zoom, 400% high contrast, OS-level dark mode.
• Forms / errors — error messages associated, field instructions clear, focus management on submit.
• Animation / motion — prefers-reduced-motion respected.

---

Integration patterns

Per-test a11y scan (Playwright)

import AxeBuilder from '@axe-core/playwright';

test('checkout has no a11y violations', async ({ page }) => {
  await page.goto('/checkout');
  const results = await new AxeBuilder({ page }).analyze();
  expect(results.violations).toEqual([]);
});

Scope to specific elements / rules:

const results = await new AxeBuilder({ page })
  .include('#main-content')
  .exclude('.legacy-widget')
  .withTags(['wcag2a', 'wcag2aa', 'wcag21aa'])
  .disableRules(['color-contrast'])  // when there's a known waiver
  .analyze();

Per-test a11y scan (Cypress)

import 'cypress-axe';

it('checkout has no a11y violations', () => {
  cy.visit('/checkout');
  cy.injectAxe();
  cy.checkA11y(null, { runOnly: ['wcag2a', 'wcag2aa', 'wcag21aa'] });
});

Standalone scan (pa11y)

pa11y https://staging.example.com/checkout --runner axe --standard WCAG2AA --reporter json > a11y.json

Useful for crawling many pages or quick spot checks outside the test framework.

Lighthouse CI

lhci autorun --collect.url=https://staging.example.com --assert.preset=lighthouse:recommended

For per-page audits including accessibility score (along with performance, best-practices, SEO).

Component-level testing

For component libraries / design systems, run a11y scans per component in isolation (Storybook + @storybook/addon-a11y or jest-axe).

---

Common WCAG criteria (and where automation helps)

WCAG Criterion (2.1 AA selection)	Automated?	Manual required?
1.1.1 Non-text content (alt)	Partial — presence yes, quality no	Yes
1.3.1 Info and relationships (semantics)	Partial	Yes
1.4.3 Contrast (minimum)	Yes	Some edge cases (gradient backgrounds)
1.4.10 Reflow (responsive)	Some	Yes
2.1.1 Keyboard	Partial — trap detection	Yes
2.4.3 Focus order	No	Yes
2.4.6 Headings and labels	Partial	Yes
2.4.7 Focus visible	Partial	Yes
3.3.1 Error identification	Partial	Yes
3.3.2 Labels or instructions	Partial	Yes
4.1.2 Name, role, value	Yes (mostly)	Edge cases
4.1.3 Status messages	Partial	Yes

WCAG 2.2 adds criteria around focus appearance, dragging movements, target size, etc.

---

Setting up an a11y program

1. Pick a conformance target — almost always WCAG 2.1 AA. WCAG 2.2 AA if regulations or audit cycle demands it.
2. Run a baseline scan with axe on critical pages — gather the gap.
3. Triage findings — categorize as blocker / major / minor. Many "issues" are duplicates of one root cause.
4. Fix the high-impact ones first — missing labels, contrast, keyboard traps.
5. Integrate axe into CI — fail the build on new violations (configure exception list for known-deferred).
6. Manual audit cycle — schedule a real-AT review (NVDA / VoiceOver / TalkBack) quarterly or per major release.
7. Train developers — give the team an a11y checklist and pair with QA.
8. Engage a third party for periodic audit if the audience is large / regulated.

---

Common Pitfalls

• Treating axe / Lighthouse score as a complete answer. They cover 30-50%.
• Adding aria-* to fix a11y without understanding semantics. "ARIA used to lie" is the most common new-bug pattern.
• Visual focus indicators removed for "clean design." Massive regression.
• Color as the sole means of conveying information — fails users with color blindness or screen readers.
• No keyboard testing. Every interactive UI must be reachable via keyboard.
• No screen-reader testing. Different screen readers handle the same markup differently.
• Disabling axe rules wholesale. Better to exempt specific elements with data-axe-exclude than to disable a rule everywhere.
• Mobile a11y ignored — touch-only assumptions miss switch-control / VoiceOver / TalkBack users.
• Form errors not associated with fields — screen readers announce form errors as unattached strings.
• Modal dialogs without focus trap — focus moves to the wrong place; users get lost.
• Treating compliance as a one-time project — accessibility ages with every UI change.
• Pretending automated scans equal legal compliance — they don't, and lawsuits have made this clear.

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Mobile accessibility specifics

iOS:

• Set accessibilityLabel / accessibilityHint / accessibilityTraits correctly.
• Test with VoiceOver (Settings → Accessibility → VoiceOver).
• For SwiftUI, .accessibilityLabel(...), .accessibilityValue(...), .accessibilityElement(children:).

Android:

• Set contentDescription (or rely on android:text for text views).
• Test with TalkBack (Settings → Accessibility → TalkBack).
• Check focus order with Accessibility Scanner.
• For Compose, Modifier.semantics { ... }.

Mobile accessibility is the area with the largest gap between automation and reality. Manual AT testing is critical.

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Compliance and legal context

• US: ADA Title III lawsuits against websites are common. WCAG 2.1 AA is the de facto standard courts use.
• US federal / contractor: Section 508 (Refresh aligned with WCAG 2.0 AA).
• EU: EAA in force June 2025 for many private sector products.
• Other regions: Canada (AODA), Australia (DDA), many countries have similar regimes.

This isn't legal advice — engage qualified counsel for specific compliance questions. The engineering side is: build to WCAG 2.1 AA (or higher), document, and periodically audit.

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Task-Specific Questions

When helping with accessibility testing, ask:

1. WCAG version target (2.0 / 2.1 / 2.2 AA)?
2. Public-facing web, internal, mobile, mix?
3. Regulatory pressure (Section 508, EAA, ADA, audit findings)?
4. Existing a11y tooling in CI?
5. Manual testing capacity (AT testers available)?
6. Component library / design system that can centralize fixes?
7. Past complaints / incidents?

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Related Skills

• visual-regression — visual diff catches what a11y catches doesn't (and vice versa); complementary.
• playwright / cypress / selenium — for integrating axe / similar into existing test runs.
• espresso / xcuitest / detox / maestro — for mobile a11y test integration.
• test-strategy — accessibility is a quality dimension; place it in strategy.
• ci-test-orchestration — for the gate hygiene.
• production-testing — for monitoring a11y regressions over time.
• ai-augmented-testing — some AI tools claim a11y wins; verify before relying.