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 afcontinue="Bausatz2a.jpg" />
  </query-continue>
  <query>
    <allfileusages>
      <f ns="6" title="File:B-Finale 2011 IMPR.jpg" />
      <f ns="6" title="File:BCBoesch-IDS-Parametrisierung.pdf" />
      <f ns="6" title="File:BRM 90130 Colourful control pannel manual.pdf" />
      <f ns="6" title="File:BRM 90130 Cutting parameter.pdf" />
      <f ns="6" title="File:BRM 90130 Gebrauchsanleitung.pdf" />
      <f ns="6" title="File:BRM 90130 Maintaince manual.pdf" />
      <f ns="6" title="File:BTListe wiki.jpg" />
      <f ns="6" title="File:Back2hack black.png" />
      <f ns="6" title="File:Banner indie.jpg" />
      <f ns="6" title="File:Basteldonnerstag.png" />
    </allfileusages>
  </query>
</api>