ErrorMessageAssociated [rule] v1.0.0

Every form-validation error message MUST be programmatically associated with its field via aria-describedby, AND the field MUST set aria-invalid='true'. Visually-adjacent error text without programmatic association is invisible to screen readers.

Checks

• @community/check-error-message-associated

Applies To

@community/type-html-artifact

Severity

critical

Severity Combination

error visible, no aria-describedby                   → BLOCK  (SC 1.3.1, 3.3.1)
error visible, no aria-invalid                       → WARN
error has both aria-describedby and aria-invalid     → PASS

Failure Mode

Screen-reader users hear the field name and value but no indication an error exists; they submit the form again with the same data and the same failure. WCAG Level A fails.

Remediation

• Render: <input id='email' aria-describedby='email-error' aria-invalid='true'> <p id='email-error' role='alert'>Enter a valid email.</p>.
• Toggle aria-invalid to false (or remove) when the user corrects the value — don't leave stale state.
• Use role='alert' (or aria-live='polite') on the error region so the message is announced when it appears, not on next focus.
• If a field has both a hint and an error, set aria-describedby='email-hint email-error' (space-separated).

Exceptions

• • Case: Server-side post-submit error page
  • Allowed When: A full re-render of the form with errors injected as adjacent text is acceptable IF aria-describedby is wired on render.

ErrorMessageAssociated [rule] v1.0.0

Every form-validation error message MUST be programmatically associated with its field via aria-describedby, AND the field MUST set aria-invalid='true'. Visually-adjacent error text without programmatic association is invisible to screen readers.

Checks

• @community/check-error-message-associated

Applies To

@community/type-html-artifact

Severity

critical

Severity Combination

error visible, no aria-describedby                   → BLOCK  (SC 1.3.1, 3.3.1)
error visible, no aria-invalid                       → WARN
error has both aria-describedby and aria-invalid     → PASS

Failure Mode

Screen-reader users hear the field name and value but no indication an error exists; they submit the form again with the same data and the same failure. WCAG Level A fails.

Remediation

• Render: <input id='email' aria-describedby='email-error' aria-invalid='true'> <p id='email-error' role='alert'>Enter a valid email.</p>.
• Toggle aria-invalid to false (or remove) when the user corrects the value — don't leave stale state.
• Use role='alert' (or aria-live='polite') on the error region so the message is announced when it appears, not on next focus.
• If a field has both a hint and an error, set aria-describedby='email-hint email-error' (space-separated).

Exceptions

• • Case: Server-side post-submit error page
  • Allowed When: A full re-render of the form with errors injected as adjacent text is acceptable IF aria-describedby is wired on render.

Applies To

@community/type-html-artifact

Severity

critical

Validates With

• @w3c/source-wcag-22

Severity Combination

error visible, no aria-describedby                   → BLOCK  (SC 1.3.1, 3.3.1)
error visible, no aria-invalid                       → WARN
error has both aria-describedby and aria-invalid     → PASS

Failure Mode

Screen-reader users hear the field name and value but no indication an error exists; they submit the form again with the same data and the same failure. WCAG Level A fails.

Remediation

• Render: <input id='email' aria-describedby='email-error' aria-invalid='true'> <p id='email-error' role='alert'>Enter a valid email.</p>.
• Toggle aria-invalid to false (or remove) when the user corrects the value — don't leave stale state.
• Use role='alert' (or aria-live='polite') on the error region so the message is announced when it appears, not on next focus.
• If a field has both a hint and an error, set aria-describedby='email-hint email-error' (space-separated).

Exceptions

• • Case: Server-side post-submit error page
  • Allowed When: A full re-render of the form with errors injected as adjacent text is acceptable IF aria-describedby is wired on render.

See Also

• @community/check-error-message-associated