Add custom Facebook Social Share descriptions for Yoast SEO for Archive pages

functions.php

<?php
/* @link https://anythinggraphic.net/yoast-seo-add-custom-social-share-images-for-archive-category-pages-in-wordpress
/* Add custom Facebook Social Share descriptions for Yoast SEO for Archive pages
----------------------------------------------------------------------------------------*/
add_filter( 'wpseo_opengraph_desc', 'ag_yoast_seo_fb_share_descriptions' );
function ag_yoast_seo_fb_share_descriptions( $desc ) {
	if( is_post_type_archive( 'posttypename' ) ) {
		$desc = 'Design and development projects by Anything Graphic.';
	}
	if( is_category( 'categoryname' ) ) {
		$desc = 'Design and development projects by Anything Graphic.';
	}
	return $desc;
}