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="Doctools2.JPG|341" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page" />
      <page pageid="8" ns="0" title="Framework for consent policies" />
      <page pageid="37" ns="0" title="Frameworks for data sharing" />
      <page pageid="302" ns="0" title="RDF Nairobi consent-ish" />
      <page pageid="324" ns="0" title="Responsible Data Hangouts" />
      <page pageid="341" ns="0" title="RDF Manila Technology/Tools" />
      <page pageid="344" ns="0" title="RDF Manila Data Quality" />
      <page pageid="348" ns="0" title="Instructions to join the RDF online discussion" />
    </pages>
  </query>
</api>