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>
    <alltransclusions gatcontinue="Myst|692" />
  </query-continue>
  <query>
    <pages>
      <page pageid="22" ns="0" title="Mohawk archive format" />
      <page pageid="102" ns="10" title="Template:Bp" />
      <page pageid="292" ns="0" title="Myst resources" />
      <page pageid="552" ns="0" title="Myst MSND resources" />
      <page pageid="562" ns="0" title="Myst WDIB resources" />
      <page pageid="572" ns="0" title="Myst CLRC resources" />
      <page pageid="612" ns="0" title="Myst RSFL resources" />
      <page pageid="632" ns="0" title="Myst HELP resources" />
      <page pageid="652" ns="0" title="Mohawk Sounds" />
      <page pageid="682" ns="0" title="Myst EXIT resources" />
    </pages>
  </query>
</api>