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="Bandwidth_utilization_SNMP.pdf" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1807" ns="6" title="File:BGP-overall.png" />
      <page pageid="16159" ns="6" title="File:BGP and PCEP Kibana.png" />
      <page pageid="7603" ns="6" title="File:BIER APP Figure.jpeg" />
      <page pageid="4879" ns="6" title="File:BIER Figure1.jpeg" />
      <page pageid="4880" ns="6" title="File:BIER Figure2.jpeg" />
      <page pageid="4881" ns="6" title="File:BIER Figure3.jpeg" />
      <page pageid="4882" ns="6" title="File:BIER Figure4.jpeg" />
      <page pageid="3967" ns="6" title="File:BMP.png" />
      <page pageid="1600" ns="6" title="File:BS.png" />
      <page pageid="1598" ns="6" title="File:BS NBR invite.png" />
    </pages>
  </query>
</api>