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="467" ns="0" title="BK2010 Architectonische basisbegrippen en gebouwenleer 2" />
      <page pageid="468" ns="0" title="BK2020 Stedenbouwkundige basisbegrippen 2" />
      <page pageid="469" ns="0" title="BK2030 Architectuur-, stedenbouw- en kunstgeschiedenis 2" />
      <page pageid="470" ns="0" title="BK2050 Bouwprocesmanagement 1" />
      <page pageid="471" ns="0" title="BK2060 Wetenschapsleer 1" />
      <page pageid="473" ns="0" title="BK2080 Handtekenen 2" />
      <page pageid="474" ns="0" title="BK2090 Vormstudie 2" />
    </pages>
  </query>
</api>