get_the_archive_description()

function get_the_archive_description() {
	if ( is_author() ) {
		$description = get_the_author_meta( 'description' );
	} elseif ( is_post_type_archive() ) {
		$description = get_the_post_type_description();
	} else {
		$description = term_description();
	}

	/**
	 * Filters the archive description.
	 *
	 * @since WP-4.1.0
	 *
	 * @param string $description Archive description to be displayed.
	 */
	return apply_filters( 'get_the_archive_description', $description );
}