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>
    <pages>
      <page pageid="1587" ns="0" title="Galant AIIGS" />
      <page pageid="1588" ns="0" title="Galant AIIGS Modellausstattungen" />
      <page pageid="923" ns="0" title="Galant AII GS" />
      <page pageid="924" ns="0" title="Galant AII GS Modellausstattungen" />
      <page pageid="822" ns="0" title="Galant EA0 Styling Hecklogos entfernen" />
      <page pageid="925" ns="0" title="Galant Sigma A120" />
      <page pageid="926" ns="0" title="Galant Sigma A120 Modellausstattungen" />
      <page pageid="843" ns="0" title="Mitsubishi Sigma" />
      <page pageid="851" ns="0" title="Mitsubishi Space Gear" />
      <page pageid="830" ns="0" title="Mitsubishi i-MiEV" />
    </pages>
  </query>
</api>