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="Telisha.png|162" />
  </query-continue>
  <query>
    <pages>
      <page pageid="13" ns="0" title="The Rift Wars" />
      <page pageid="76" ns="0" title="Jorta Gutthammer" />
      <page pageid="83" ns="0" title="Dunc &quot;The Fish&quot; Poisson" />
      <page pageid="117" ns="0" title="Kinnoch" />
      <page pageid="122" ns="0" title="Kelauklyth" />
      <page pageid="123" ns="0" title="Mador Kheb" />
      <page pageid="130" ns="0" title="Kardan Deerstalker" />
      <page pageid="137" ns="0" title="Part 11: Kal-Ne-Moz" />
      <page pageid="160" ns="0" title="Part 36: Wizard Towers and Magical Doors" />
      <page pageid="162" ns="0" title="Part 37: Secret Wizard Business" />
    </pages>
  </query>
</api>