Install WordPress Plugin

Installs a plugin on a connected WordPress site from a wordpress.org slug (the plugin directory name, such as wordpress-seo) or a zip URL, and optionally activates it.

Installing and activating are reported separately: if the files land but activation fails you get the real activation error, not a blanket failure. When a plugin that was NOT already on the site fails to activate, its files are removed again (rolled_back=true) so nothing dead is left behind; pass keep_on_failure=true to keep them for debugging.

Page cache plugins need wp-config.php and wp-content to be writable, and some hosts refuse third-party cache plugins through a must-use plugin of their own. Both are host limits that no retry fixes; wordpress_performance reports them, and install_recommended=false means a cache plugin cannot work on that site.