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 alcontinue="Journal_Citation_Reports" />
  </query-continue>
  <query>
    <alllinks>
      <l ns="0" title="Doktor" />
      <l ns="0" title="Dom studencki" />
      <l ns="0" title="ECTS (European Credit Transfer and Accumulation System)" />
      <l ns="0" title="Efekty kształcenia" />
      <l ns="0" title="Encyklopedia" />
      <l ns="0" title="European Reference Index for the Humanities (ERIH)" />
      <l ns="0" title="Fundusz Pomocy Studentom" />
      <l ns="0" title="Impact Factor (IF)" />
      <l ns="0" title="Institute for Scientific Information (ISI)" />
      <l ns="0" title="Jednolite studia magisterskie" />
    </alllinks>
  </query>
</api>