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>
    <allfileusages gafcontinue="Ceps.png|2665" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1192" ns="0" title="Bundesministerium der Finanzen" />
      <page pageid="1346" ns="0" title="Lobbyisten in Ministerien" />
      <page pageid="1598" ns="0" title="Daniel Bahr" />
      <page pageid="1854" ns="3004" title="Archiv Kommentar:Aktuelle Story Archiv" />
      <page pageid="2015" ns="0" title="Bundesvereinigung der Deutschen Arbeitgeberverbände" />
      <page pageid="2369" ns="3003" title="Archiv:Daniel Caspary" />
      <page pageid="2671" ns="0" title="Centre for Economic Policy Research" />
      <page pageid="2678" ns="104" title="Entwurf:Bundesverband Erneuerbare Energien e.V." />
    </pages>
  </query>
</api>