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="Disambig|2777" />
  </query-continue>
  <query>
    <pages>
      <page pageid="13" ns="0" title="The Tone Rangers" />
      <page pageid="181" ns="0" title="Crash" />
      <page pageid="746" ns="0" title="The Beagles" />
      <page pageid="1011" ns="0" title="Sgt. Pepper&#039;s Lonely Hearts Club Band" />
      <page pageid="1050" ns="0" title="The Jolly Green Giants" />
      <page pageid="1255" ns="0" title="Mystery" />
      <page pageid="1454" ns="0" title="Mayhem" />
      <page pageid="1459" ns="0" title="Linda Moon" />
      <page pageid="1548" ns="0" title="Spittle" />
      <page pageid="1653" ns="0" title="Sugar Kane" />
    </pages>
  </query>
</api>