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>
    <alllinks galcontinue="BT_Shield_v2.2" />
  </query-continue>
  <query>
    <pages>
      <page ns="0" title="BT Shield v2.1" missing="" />
      <page pageid="956" ns="0" title="BB Arduino Capes" />
      <page pageid="1498" ns="0" title="BL18 ECG Maven" />
      <page pageid="1091" ns="0" title="BLE Bee" />
      <page pageid="347" ns="0" title="BMP085 DIGITAL PRESSURE SENSOR MODULE" />
      <page pageid="302" ns="0" title="BTBee" />
      <page pageid="300" ns="0" title="BTBee Pro" />
      <page pageid="201" ns="0" title="BT BoosterPack" />
      <page pageid="153" ns="0" title="BT Shield (Master Slave)" />
      <page pageid="149" ns="0" title="BT Shield (Slave)" />
    </pages>
  </query>
</api>