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="Duchy_of_Urnst_Arms.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="3015" ns="6" title="File:Blackrazor.jpg" />
      <page pageid="3027" ns="6" title="File:Blackrazor Guild Arms.png" />
      <page pageid="3241" ns="6" title="File:Blackrazors Banner.png" />
      <page pageid="3140" ns="6" title="File:Carac.jpg" />
      <page pageid="2978" ns="6" title="File:Celwynvian.png" />
      <page pageid="2982" ns="6" title="File:Cocyrdavarin.jpeg" />
      <page pageid="2552" ns="6" title="File:Crest of OB.jpg" />
      <page pageid="3484" ns="6" title="File:DonnabellaFiasco.jpeg" />
      <page pageid="3000" ns="6" title="File:Draft Geoff.png" />
      <page pageid="3462" ns="6" title="File:Duchy Urnst.jpg" />
    </pages>
  </query>
</api>