You are looking at the HTML representation of the XML format.
HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allimages gaifrom="250px-Jorah-Mormont-game-of-thrones.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="31" ns="6" title="File:250px-Arya-stark.jpg" />
      <page pageid="32" ns="6" title="File:250px-Baelish.jpg" />
      <page pageid="33" ns="6" title="File:250px-Branstark.jpg" />
      <page pageid="34" ns="6" title="File:250px-Catelyn-stark-michelle-fairley-helen-sloan.jpg" />
      <page pageid="35" ns="6" title="File:250px-Cersei-lannister-lena-headey-helen-sloan.jpg" />
      <page pageid="36" ns="6" title="File:250px-EddardStark.jpg" />
      <page pageid="54" ns="6" title="File:250px-GendryInfobox.jpg" />
      <page pageid="37" ns="6" title="File:250px-Jaime Lannister.jpg" />
      <page pageid="38" ns="6" title="File:250px-Joffrey throne season 2.jpg" />
      <page pageid="39" ns="6" title="File:250px-Jon-Snow-Kit-Harington 510.jpg" />
    </pages>
  </query>
</api>