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>
    <alltransclusions gatcontinue="ColumnForMiscellanea" />
  </query-continue>
  <query>
    <pages>
      <page pageid="3098" ns="10" title="Template:Box-Видання" />
      <page pageid="3095" ns="10" title="Template:Box-Видання ВУАМ" />
      <page pageid="3086" ns="10" title="Template:Box-Виставки" />
      <page pageid="3091" ns="10" title="Template:Box-Виставки ВУАМ" />
      <page pageid="3084" ns="10" title="Template:Box-Відвідувачам" />
      <page pageid="3090" ns="10" title="Template:Box-Новини" />
      <page pageid="3093" ns="10" title="Template:Box-Новини ВУАМ" />
      <page pageid="3097" ns="10" title="Template:Box-Статті" />
      <page pageid="3094" ns="10" title="Template:Box-Статті ВУАМ" />
      <page pageid="3089" ns="10" title="Template:ColumnFor" />
    </pages>
  </query>
</api>