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>
    <alltransclusions gatcontinue="Languages|22" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Hauptseite" />
      <page pageid="7" ns="0" title="Der Gruene Autoupdater" />
      <page pageid="14" ns="0" title="AutoUpdater/en" />
      <page pageid="15" ns="0" title="Race07 Hilfe &amp; Tipps" />
      <page pageid="16" ns="0" title="Race07 Bugs/en" />
      <page pageid="17" ns="0" title="Hauptseite/en" />
      <page pageid="19" ns="0" title="Event/en" />
      <page pageid="20" ns="0" title="Race07 Painting" />
      <page pageid="71" ns="0" title="Boxenstopp (Begriffsklärung)" />
      <page pageid="76" ns="12" title="Hilfe:Begriffsklärung" />
    </pages>
  </query>
</api>