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>
    <pages>
      <page pageid="475" ns="106" title="MP:Le je à l&#039;œuvre" />
      <page pageid="485" ns="106" title="MP:Comptes rendus" />
      <page pageid="486" ns="106" title="MP:Comptes rendus MPAPA" />
      <page pageid="487" ns="106" title="MP:Comptes rendus 2015" />
      <page pageid="488" ns="106" title="MP:Comptes rendus 2014" />
      <page pageid="498" ns="106" title="MP:Cahier Le Je à l&#039;œuvre" />
      <page pageid="584" ns="0" title="Comptes rendus MPAPA" />
      <page pageid="928" ns="0" title="Les15ans" />
      <page pageid="949" ns="0" title="Groupe lecture" />
      <page pageid="952" ns="0" title="Comptes rendus des réunions MPAPA" />
    </pages>
  </query>
</api>