You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <tags>
      <tag name="mobile edit" displayname="Mobilredigering" description="Redigeringer gjort fra mobil (web eller app)" hitcount="1" />
      <tag name="mobile web edit" displayname="Mobilwebredigering" description="Redigering gjort fra det mobiltilpassede nettstedet" hitcount="1" />
      <tag name="mobile app edit" displayname="Mobile app edit" description="Edits made from mobile apps" hitcount="0" />
    </tags>
  </query>
</api>