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="Cppxfel_Merging_statistics" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="72" ns="0" title="CSPAD Pattern" />
      <p pageid="45" ns="0" title="Category handler" />
      <p pageid="119" ns="0" title="Cctbx.prime" />
      <p pageid="122" ns="0" title="Configure cctbx.xfel from existing Phenix install" />
      <p pageid="124" ns="0" title="Cppxfel" />
      <p pageid="131" ns="0" title="Cppxfel Final Merge" />
      <p pageid="126" ns="0" title="Cppxfel Indexing" />
      <p pageid="141" ns="0" title="Cppxfel Indexing with DIALS" />
      <p pageid="128" ns="0" title="Cppxfel Initial Orientation Matrix Refinement" />
      <p pageid="132" ns="0" title="Cppxfel Installation" />
    </allpages>
  </query>
</api>