public function __construct() {
		// Add query vars.
		add_filter( 'query_vars', array( $this, 'add_query_vars' ), 0 );

		// Register auth endpoint.
		add_action( 'init', array( __CLASS__, 'add_endpoint' ), 0 );

		// Handle auth requests.
		add_action( 'parse_request', array( $this, 'handle_auth_requests' ), 0 );
	}