Error Messages as a Computable Contract: Text, Bound, Flagged, Corrective

WCAG 3.3.1 and 3.3.3 plus MDN's aria-invalid and aria-describedby split a form error into four clauses. Three can be checked in the DOM; the fourth needs judgment.

Named but Not Known: Measuring the Gap Between Field Names and Machine Purpose

A static audit separating a field's programmatic name from its declared machine purpose, plus two gates agents can compute from server-sent markup.