JS Morisset

Extends the WordPress REST API post, term, and user query results:
<ul>
<li>The <code>html</code> array includes HTML formatted meta tags and Schema JSON-LD (aka LD+JSON) scripts, as they appear in the webpage head section.</li>
<li>The <code>json</code> array provides Schema JSON-LD (aka LD+JSON) scripts in their decoded format.</li>
<li>The <code>parts</code> array offers meta tag attributes (aka “the parts”) as arrays, making it easier to find and use specific meta tag values.</li>
</ul>
There is no add-on settings page for this plugin – simply install and activate the plugin.

<h3>WPSSO Core Required</h3>
WPSSO REST API is an add-on for the <a href="https://wordpress.org/plugins/wpsso/" rel="ugc">WPSSO Core plugin</a>, which creates extensive and complete structured data to present your content at its best for social sites and search results – no matter how URLs are shared, reshared, messaged, posted, embedded, or crawled.

WPSSO REST API

Extends the WordPress REST API post, term, and user query results with an array of meta tags and Schema JSON-LD markup.

Philipp Speck

This plugin will give you the ability to use the <code>excerpt</code> as <code>meta description</code> for any post or page. From now you are able to control the description of your site which will be displayed on the search engine results pages. 
By activation the plugin enables the excerpt for static edit pages in admin area.
Related Links
<ul>
<li><a href="http://www.typomedia.org/wordpress/plugins/wordpress-meta-description/" title="Homepage of WordPress Meta Description" rel="nofollow ugc">Homepage</a></li>
<li><a href="https://wordpress.org/extend/plugins/wordpress-meta-description/changelog/" title="Changelog for WordPress Meta Description" rel="ugc">Changelog</a></li>
<li><a href="https://wordpress.org/extend/plugins/wordpress-meta-description/faq/" title="FAQ for WordPress Meta Description" rel="ugc">Questions</a></li>
<li><a href="http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35264#1" title="Create good meta descriptions" rel="nofollow ugc">Information</a></li>
</ul>
Note: 
Before installing or upgrading new plugins, please backup your database first!

WordPress Meta Description

With this plugin you can control the text which will be shown as description on the search engine results pages.

WPSSO REST API vs WordPress Meta Description