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>
    <allredirects garcontinue="Launch_Phase" />
  </query-continue>
  <query>
    <pages>
      <page pageid="262" ns="0" title="Class Analysis - realisation" />
      <page pageid="286" ns="0" title="Common Activities" />
      <page pageid="292" ns="0" title="Definitions in EUDP" />
      <page pageid="342" ns="0" title="Design Constraints Analysis" />
      <page pageid="345" ns="0" title="Design Partitioning" />
      <page pageid="310" ns="0" title="EUDP Roadmap" />
      <page pageid="283" ns="0" title="Final Product Acceptance" />
      <page pageid="220" ns="0" title="General Analysis" />
      <page pageid="244" ns="0" title="General Architecture Design" />
      <page pageid="266" ns="0" title="Interface Analysis - realisation" />
    </pages>
  </query>
</api>