a11y-checklist

Severity classification (drives the gate — critical/serious block, minor does not)

• critical/serious (blocks verify-gate.sh): missing accessible name on an interactive control, keyboard trap, focus not moved/trapped correctly in a modal dialog, insufficient color contrast on body text, missing form label association, content that only conveys meaning via color.
• minor (reported, does not block): redundant alt text, non-ideal heading hierarchy on a page that is still navigable, a title attribute duplicating visible text.

Mechanical checks (axe-core catches these — a11y-auditor just triages severity)

• Every interactive element has an accessible name (button text, aria-label, or associated <label> — see the email input in SubscribeDialog.tsx).
• Every image conveying information has alt text; every decorative image has alt="".
• Focus is visible on every interactive element (focus-visible:ring-*, never outline-none alone — see component-conventions skill).
• Radix Dialog primitives handle focus trap and aria-modal automatically — do not reimplement focus trapping manually; a hand-rolled dialog is a common source of critical findings.
• Color contrast meets WCAG AA (4.5:1 normal text, 3:1 large text) — check new @theme tokens against both light and dark rendering, not just one.

Judgment calls (a11y-auditor escalates these to model: sonnet instead of guessing)

• Whether alt text is meaningful (not just present).
• Whether a complex widget's aria-* roles fully match its actual keyboard behavior.
• Whether reading order (DOM order vs visual order) creates a confusing experience for screen reader users, even if no individual axe rule fires.