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>
    <alllinks galcontinue="Operativer_Prozessverantwortlicher" />
  </query-continue>
  <query>
    <pages>
      <page pageid="5" ns="0" title="BPMN-Stakeholder" />
      <page pageid="50" ns="0" title="BPMNPoster" />
      <page pageid="27" ns="0" title="BPMN 2.0" />
      <page pageid="16" ns="0" title="BPMN Best Practices" />
      <page pageid="9" ns="0" title="Enterprise Architect" />
      <page pageid="97" ns="0" title="IT Service Management mit ITIL und BPMN" />
      <page pageid="57" ns="0" title="Initiatoren" />
      <page pageid="25" ns="0" title="Konsistenz von Prozessmodellen" />
      <page pageid="60" ns="0" title="Linksammlung" />
      <page pageid="84" ns="0" title="Nützlichkeit von Referenzmodellen" />
    </pages>
  </query>
</api>