Skill Wiki
Validate Required Fields
@community/step-validate-required-fields
$ prime install @community/step-validate-required-fieldsProjection
Always in _index.xml · the agent never has to ask for this.
ValidateRequiredFields [step] v1.0.0
Loaded when retrieval picks the atom as adjacent / supporting.
ValidateRequiredFields [step] v1.0.0
signature: (form: HTMLFormElement | FormDataObject) -> ValidationResult effect: read-only
Errors
- InvalidFormElement
- NoFieldsFound
Body
For each field F in form.fields:
1. Check `required` attribute or `data-required` flag.
2. If required AND F.value is empty (undefined, null, "", or whitespace-only):
record violation:
{ field-id: F.id, field-name: F.name, message: localizedMessage(F, 'required') }
3. If F has `pattern` attribute AND F.value does not match:
record violation with message from F.dataset.patternError or default.
4. If F.type == 'email' AND F.value does not match RFC-5322-compatible regex:
record violation.
5. If F has `minlength` AND F.value.length < minlength:
record violation.
Aggregation rules:
- For each violation, set ARIA: F.setAttribute('aria-invalid', 'true')
and link to error message via F.setAttribute('aria-describedby', errorId).
- Move keyboard focus to the FIRST violating field on submit attempt.
- Announce summary via aria-live="assertive" region: "5 errors prevented submission. First error: ..."
- Inline error message must be visually adjacent to the field (NOT only in a top banner).
Return ValidationResult = {
valid: boolean, // true iff no violations
violations: Violation[], // ordered by DOM order
first-invalid: HTMLElement | null
}
Preconditions
- form has been initialized in the DOM with semantic /