Go to ShadowSync SEO → robots.txt.
Edit the file in the box and save. Before saving, the plugin checks every line: a line without a colon, or a directive it does not recognise, is rejected with the line number. Valid directives are User-agent, Disallow, Allow, Sitemap, Crawl-delay and Host.
The default file blocks /wp-admin/ (except admin-ajax.php) and points to your sitemap. Reset puts it back.
AI crawler rules
Below the editor, click a bot to insert an Allow or Disallow rule for it. For switches instead of rules, use AI crawler access.
WordPress only serves this file when there is no real robots.txt file in your site’s root folder. If your changes do not show at yoursite.com/robots.txt, ask your host to remove the physical file.