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>
    <alllinks>
      <l ns="0" title="Backup" />
      <l ns="0" title="Basic Configuration" />
      <l ns="0" title="Building and maintaining a contrib Zentyal module" />
      <l ns="0" title="Bulk LDAP Password Change" />
      <l ns="0" title="CA, SSL, Apache, Mail &amp; Zarafa" />
      <l ns="0" title="Captive Portal" />
      <l ns="0" title="Certification authority (CA)" />
      <l ns="0" title="Certified hardware" />
      <l ns="0" title="Clamav unofficial sigs" />
      <l ns="0" title="Coding Style" />
    </alllinks>
  </query>
  <query-continue>
    <alllinks alcontinue="Commit_Messages" />
  </query-continue>
</api>