<form data-raykoi> on the page — handles submission, validation, CAPTCHA, and the success/error message automatically.
.raykoi-field-error and data-raykoi-error-type (required/pattern/minLength/…) on field error containers, .raykoi-message and data-raykoi-state="success"|"error" on the message container.
Every data-* attribute this runtime reads is in Attributes; the full lifecycle event list is in Events.