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 afcontinue="Wiki_promo_image_community.jpg|1" />
  </query-continue>
  <query>
    <allfileusages>
      <f ns="6" title="File:Lords-Mobile-Colosseum-Rankings.jpg" />
      <f ns="6" title="File:Monopoly Dice Rolls Social Connect.jpg" />
      <f ns="6" title="File:Public empowerment examples of best practices.pdf" />
      <f ns="6" title="File:Roblox App Store.png" />
      <f ns="6" title="File:Roblox Gift Card.png" />
      <f ns="6" title="File:Roblox Robux Safe Methods.jpg" />
      <f ns="6" title="File:Robux-Safety-Shield.jpg" />
      <f ns="6" title="File:TSTO Donut.png" />
      <f ns="6" title="File:Warframe Maroo Bazaar.png" />
      <f ns="6" title="File:Wiki promo image.jpg" />
    </allfileusages>
  </query>
</api>