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="Software_webcam|621" />
  </query-continue>
  <query>
    <pages>
      <page pageid="500" ns="0" title="FAQ Weewx" />
      <page pageid="547" ns="0" title="FAQ WX" />
      <page pageid="565" ns="0" title="VUE" />
      <page pageid="730" ns="0" title="Fine Offset (modelos actuales)" />
      <page pageid="732" ns="0" title="ISS-FINEOFFSET" />
      <page pageid="771" ns="0" title="Reinicio Precipitación WS2900" />
      <page pageid="785" ns="0" title="CONSOLAS-FINEOFFSET" />
      <page pageid="789" ns="0" title="CCL Electronics" />
      <page pageid="793" ns="0" title="Cumulus MX" />
      <page pageid="832" ns="0" title="&#039;&#039;&#039;Código de estación&#039;&#039;&#039;" />
    </pages>
  </query>
</api>