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-continue>
    <allfileusages gafcontinue="Bradbury.jpg|191" />
  </query-continue>
  <query>
    <pages>
      <page pageid="30" ns="0" title="Richard of Hallcaster" />
      <page pageid="97" ns="0" title="Liste der Premierminister" />
      <page pageid="157" ns="0" title="Liberal Democrats" />
      <page pageid="167" ns="0" title="Liste der Schatzkanzler" />
      <page pageid="175" ns="0" title="Liste der Innenminister" />
      <page pageid="184" ns="0" title="Liste der Außenminister" />
      <page pageid="191" ns="0" title="Liste der stellvertretenden Premierminister" />
      <page pageid="241" ns="0" title="Liste der Speaker" />
      <page pageid="398" ns="0" title="Mosambabo" />
    </pages>
  </query>
</api>