The `auro-checkbox` component follows native HTML checkbox semantics. This page documents the ARIA attributes, screen reader behavior, and other accessibility features built into the component. For keyboard interaction details, see the Keyboard Behavior page. ARIA Roles and Attributes Checkbox Group The `` element uses a `

` with a `

` internally, providing native grouping semantics. These attributes are applied to that shadow-DOM `

`, **not** to the `` host element: | Attribute | Value | Description | |---|---|---| | `role` | `group` (implicit via `fieldset`) | Groups related checkboxes together. There is no ARIA `checkboxgroup` role, so the `

`'s implicit `group` role is used as-is. | | `aria-invalid` | `true` | Present only while the group is in an invalid state. The attribute is **omitted entirely** when the group is valid — it is never set to `false`. | | `aria-describedby` | id reference | Points at the `id` of the group's help-text/error element, so assistive technology can associate the message with the group on demand rather than relying only on the one-time live-region announcement. | Checkbox Each `` renders a native `` inside its shadow DOM: | Attribute | Value | Description | |---|---|---| | `type` | `checkbox` | Native checkbox input type. | | `aria-checked` | `true` / `false` | Reflects the checked state of the checkbox. | | `aria-disabled` | `true` / `false` | Indicates whether the checkbox is disabled. | | `aria-invalid` | `true` | Mirrored onto each checkbox from the group while the group is invalid, and removed when it becomes valid. Omitted rather than set to `false`. | Why the invalid state appears twice While the group is invalid, `aria-invalid` is set on both the `

` and every individual ``. This is intentional: some assistive-technology and browser combinations announce a container's invalid state only when focus first enters the group, so mirroring the state onto each checkbox keeps it conveyed as focus moves through the options. The `checkbox` role is in `aria-invalid`'s supported-role list in every ARIA version, so the per-checkbox placement is unambiguous. The group-level placement is worth one note: `aria-invalid` is a global attribute in ARIA 1.1, applicable to any role including `group`, but ARIA 1.2 deprecates that global use in favor of a supported-role list that does not include `group`. Keeping it on the `

` is a deliberate choice — it is not a *prohibited* attribute for `group`, current axe-core resolves it as global and reports no violation, and it gives the group a real invalid signal that would otherwise be lost. This is covered by an automated axe assertion in the component's test suite so that a future change in tooling surfaces here rather than in a consumer's audit. Attribute placement `aria-invalid` is applied to the internal `

`, not to the `` host element. Do not write CSS selectors or test assertions against `auro-checkbox-group[aria-invalid]`; target the `part="checkbox-group"` fieldset or read the `validity` property instead. Screen Reader Announcements - **Focus** — When focus moves to a checkbox, the screen reader announces the checkbox label, its checked/unchecked state, and role ("checkbox"). - **State change** — Toggling the checkbox announces the new state ("checked" or "unchecked"). - **Group context** — The legend text provides group context when navigating between groups. - **Error** — When validation fails, the error message is announced immediately via the help text's `role="alert"` live region, and stays discoverable afterward through the group's `aria-describedby` association. - **Invalid state** — While the group is invalid, entering it or moving between its checkboxes conveys the invalid state. Accessible Labels - The `legend` slot content provides the accessible group label via the native `

` element. - Each checkbox's default slot content provides its individual accessible label. - A label is required for each checkbox. Without it, assistive technology users will not have context for what the checkbox controls. - The `(optional)` label is automatically appended when the `required` attribute is not set. Form Participation The `` participates in form validation and submission. When used inside a `

` or ``, checked checkbox values are included in the form data.