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>
    <allimages gaicontinue="Bill_to_withdraw_jurisdiction_re_draft.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="409" ns="6" title="File:0502171447.jpg" />
      <page pageid="345" ns="6" title="File:08-964 Bilski patent amicus brief.pdf" />
      <page pageid="564" ns="6" title="File:16-1436-16A1190-16A1191-ac-EFELDF.pdf" />
      <page pageid="775" ns="6" title="File:16-1436tsacEagleForumELDF.pdf" />
      <page pageid="379" ns="6" title="File:2017 Eagle Forum Education Intern Application.pdf" />
      <page pageid="408" ns="6" title="File:24438.jpg" />
      <page pageid="1006" ns="6" title="File:800px-Train moving.jpg" />
      <page pageid="834" ns="6" title="File:American History Final Exam Cartoon.jpg" />
      <page pageid="778" ns="6" title="File:Amicus brief against AIA 16-712.pdf" />
      <page pageid="410" ns="6" title="File:Amicus brief in support of inventors 16-1271.pdf" />
    </pages>
  </query>
</api>