<http://schema.org/description>
"A Google Groups thread has a fairly simple but educational FAQ on how the \"Set Crawl Rate\" feature works in Google Webmaster Tools.In short, you can only set the crawl rate for a site on the domain or"^^<http://www.w3.org/2001/XMLSchema#string>
<https://www.seroundtable.com/archives/015132.html>