Accessibility & AI.

The things that make websites accessible to humans with disabilities are the SAME things that make them readable by any machine.

This isn’t coincidental. It’s fundamental.

Both screen readers and AI agents face identical challenges: they can’t see visual design, they can’t hover, they can’t infer from context. They need explicit structure, semantic meaning, and clear declarations of intent.

When you fix accessibility, you simultaneously fix agent compatibility.

Why WCAG Matters for AI

WCAG 2.1 AA (Web Content Accessibility Guidelines, Level AA) is the legal standard for accessibility in most jurisdictions. It’s also, unintentionally, the perfect specification for AI agent compatibility.

Semantic HTML

WCAG requires: Use appropriate HTML elements for their intended purpose.

Why humans need it: Screen readers announce element roles (“navigation”, “main content”, “article”).

Why agents need it: Semantic elements declare purpose explicitly. <nav> means navigation. <main> means primary content. No guessing.

Example:

<!-- Bad -->
<div class="header">
  <div class="nav">Links</div>
</div>

<!-- Good -->
<header>
  <nav>Links</nav>
</header>

Heading Hierarchy

WCAG requires: Proper heading structure (h1→h2→h3, no skipping levels).

Why humans need it: Screen reader users navigate by headings to find content quickly.

Why agents need it: Heading hierarchy shows content structure and relationships.

Alt Text

WCAG requires: Descriptive alt text on all images.

Why humans need it: Vision-impaired users understand image content through descriptions.

Why agents need it: AI vision models use alt text to verify and enhance image understanding.

Form Labels

WCAG requires: Explicit labels connected to form inputs.

Why humans need it: Screen readers announce what each field is for.

Why agents need it: Agents filling forms need to know which field is email vs. phone vs. name.

The Pattern

Every WCAG requirement has dual benefits:

The convergence is complete: good accessibility IS good agent compatibility.

Common Accessibility/Agent Fixes

1. Proper Button Markup

Accessible AND agent-compatible:

<button type="submit" disabled aria-disabled="true">
  Submit Order
</button>

Both screen readers and agents know this button is currently disabled.

2. Meaningful Link Text

Bad:

<a href="/products">Click here</a>

Good:

<a href="/products">Browse our product catalog</a>

Screen reader users and agents both benefit from descriptive link text.

3. Form Validation

Accessible AND agent-compatible:

<label for="email">Email</label>
<input type="email" id="email" required aria-required="true"
       aria-invalid="false" aria-describedby="email-error">
<span id="email-error" role="alert" aria-live="polite"></span>

Both humans and agents understand requirements, current state, and errors.

The Business Case

Accessibility used to be: Legal compliance + inclusive design

Accessibility now is: Legal compliance + inclusive design + AI agent compatibility

Organizations delaying accessibility work are now triply behind:

1. Legal risk (ADA, AODA, etc.)
2. Excluding users with disabilities
3. Opaque to AI agents

Fixing accessibility simultaneously addresses all three.

Implementation Priority

Start with WCAG 2.1 Level AA compliance:

The goal: WCAG 2.1 AA compliance = Agent compatibility.

→ Back to Key Principles → Next: Explicit Over Implicit → Get Accessibility Audit