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>
    <allpages apcontinue="En_ARTICLES_SEARCH.sql" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="404" ns="0" title="COUNTRIES.sql" />
      <p pageid="1419" ns="0" title="Cart onepage order manager" />
      <p pageid="1386" ns="0" title="Catalog manager edit pic" />
      <p pageid="1385" ns="0" title="Catalog manager upload many pics" />
      <p pageid="1398" ns="0" title="Catalog part info view" />
      <p pageid="1381" ns="0" title="Catalog price view" />
      <p pageid="1380" ns="0" title="Contact form" />
      <p pageid="1387" ns="0" title="Cross" />
      <p pageid="1389" ns="0" title="Cross add" />
      <p pageid="427" ns="0" title="En ARTICLES.sql" />
    </allpages>
  </query>
</api>