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>
    <allredirects garcontinue="Error_Page_Handling" />
  </query-continue>
  <query>
    <pages>
      <page ns="0" title="Domain Name Management" missing="" />
      <page pageid="156" ns="0" title="Backup &amp; Restore Databases - MS SQL" />
      <page pageid="4" ns="0" title="Client Control Panel" />
      <page pageid="142" ns="0" title="Connecting to Database - MS SQL" />
      <page pageid="30" ns="0" title="Control Panels" />
      <page pageid="650" ns="0" title="DNS (Name Servers)" />
      <page pageid="56" ns="0" title="DNS - Name Servers" />
      <page pageid="43" ns="0" title="Edition &amp; Versions - ColdFusion" />
      <page pageid="11" ns="0" title="Editions - MS SQL" />
      <page pageid="52" ns="0" title="Error Handling" />
    </pages>
  </query>
</api>