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>
    <allmessages>
      <message name="ipb-blockingself" xml:space="preserve">You are about to block yourself! Are you sure you want to do that?</message>
      <message name="ipb-blocklist" xml:space="preserve">Blokeaketak ikusi</message>
      <message name="ipb-blocklist-contribs" xml:space="preserve">$1(r)en ekarpenak</message>
      <message name="ipb-change-block" xml:space="preserve">Lankidea honako balioekin bir-blokeatu</message>
      <message name="ipb-confirm" xml:space="preserve">Blokeoa baieztatu</message>
      <message name="ipb-confirmhideuser" xml:space="preserve">You are about to block a user with &quot;hide user&quot; enabled. This will suppress the user's name in all lists and log entries. Are you sure you want to do that?</message>
      <message name="ipb-default-expiry" xml:space="preserve" />
      <message name="ipb-disableusertalk" xml:space="preserve">Prevent this user from editing their own talk page while blocked</message>
      <message name="ipb-edit-dropdown" xml:space="preserve">Blokeatzeko arrazoiak aldatu</message>
      <message name="ipb-hardblock" xml:space="preserve">Prevent logged-in users from editing from this IP address</message>
      <message name="ipb-needreblock" xml:space="preserve">$1 dagoeneko blokeaturik dago. Ezarpenak aldatu nahi al dituzu?</message>
      <message name="ipb-otherblocks-header" xml:space="preserve">Bestelako {{PLURAL:$1|blokeoa|blokeoak}}</message>
      <message name="ipb-unblock" xml:space="preserve">Erabiltzaile izen edo IP helbide bati blokeoa kendu</message>
      <message name="ipb-unblock-addr" xml:space="preserve">$1 lankide edo IP helbideari blokeoa baliogabetu</message>
    </allmessages>
  </query>
</api>