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 arcontinue="BayPrixces_Condito,_Arch_Mage_of_the_Brotherhood_of_Sorcery|4129" />
  </query-continue>
  <query>
    <allredirects>
      <r fromid="2421" ns="0" title="Baal-Naygash (undead)" />
      <r fromid="5793" ns="0" title="Barbarian Guild" />
      <r fromid="5891" ns="0" title="Barbarian Guild" />
      <r fromid="6392" ns="0" title="Barnum is here, polishing his wares lovingly" />
      <r fromid="6624" ns="0" title="BatMUD" />
      <r fromid="6932" ns="0" title="BatMUD" />
      <r fromid="5564" ns="0" title="Battleaxe of the Barbarian Lords" />
      <r fromid="1633" ns="0" title="BayPrixces Condito, Arch Mage and Relic Collector" />
      <r fromid="1632" ns="0" title="BayPrixces Condito, Arch Mage of the Brotherhood of Sorcery" />
      <r fromid="1828" ns="0" title="BayPrixces Condito, Arch Mage of the Brotherhood of Sorcery" />
    </allredirects>
  </query>
</api>