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="Barrel_Belly|37353" />
  </query-continue>
  <query>
    <pages>
      <page pageid="31617" ns="0" title="BTB" />
      <page pageid="31613" ns="0" title="Barbarous thorn shield" />
      <page pageid="31432" ns="0" title="Prismatic Barrel Belly" />
      <page pageid="37350" ns="0" title="Cool Barrel Belly" />
      <page pageid="31614" ns="0" title="Bts" />
      <page pageid="31616" ns="0" title="Barbarous thorn blade" />
      <page pageid="31618" ns="0" title="Btb" />
      <page pageid="37352" ns="0" title="Dusky Barrel Belly" />
      <page pageid="37351" ns="0" title="Divine Barrel Belly" />
      <page pageid="31615" ns="0" title="BTS" />
    </pages>
  </query>
</api>