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="Placeholder.png|23" />
  </query-continue>
  <query>
    <pages>
      <page pageid="5" ns="0" title="Banausic Smelter" />
      <page pageid="12" ns="0" title="Alluring Whelp" />
      <page pageid="14" ns="0" title="Audacious Accuser" />
      <page pageid="16" ns="0" title="Based Attorney" />
      <page pageid="17" ns="0" title="Belliferous Malison" />
      <page pageid="18" ns="0" title="Bemused Tutor" />
      <page pageid="20" ns="0" title="Benign Shamus" />
      <page pageid="21" ns="0" title="Brazen Hooligan" />
      <page pageid="22" ns="0" title="Cantankerous Litigator" />
      <page pageid="62" ns="0" title="Swag Bells" />
    </pages>
  </query>
</api>