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="Col-begin|321" />
  </query-continue>
  <query>
    <pages>
      <page pageid="181" ns="0" title="Logic Live" />
      <page pageid="187" ns="0" title="Logical graph" />
      <page pageid="301" ns="0" title="Peirce&#039;s law" />
      <page pageid="312" ns="0" title="Relation theory" />
      <page pageid="313" ns="0" title="Triadic relation" />
      <page pageid="314" ns="0" title="Sign relation" />
      <page pageid="315" ns="0" title="Minimal negation operator" />
      <page pageid="316" ns="0" title="Multigrade operator" />
      <page pageid="317" ns="0" title="Parametric operator" />
      <page pageid="320" ns="0" title="Ampheck" />
    </pages>
  </query>
</api>