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>
    <pageswithprop gpwpcontinue="16" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page" contentmodel="wikitext" pagelanguage="en" touched="2017-04-13T16:04:31Z" lastrevid="4195" counter="222273" length="3030" />
      <page pageid="4" ns="0" title="Phosphatase classification" contentmodel="wikitext" pagelanguage="en" touched="2017-04-13T23:51:56Z" lastrevid="4204" counter="135119" length="6783" />
      <page pageid="7" ns="0" title="Phosphatase Family Myotubularin" contentmodel="wikitext" pagelanguage="en" touched="2016-09-09T13:54:02Z" lastrevid="3883" counter="57106" length="6503" />
      <page pageid="8" ns="0" title="Phosphatase Family CDC25" contentmodel="wikitext" pagelanguage="en" touched="2015-11-20T00:45:41Z" lastrevid="3485" counter="46954" length="2406" />
      <page pageid="9" ns="0" title="Phosphatase Family SSU72" contentmodel="wikitext" pagelanguage="en" touched="2016-11-12T18:20:55Z" lastrevid="3973" counter="13067" length="1050" />
      <page pageid="10" ns="0" title="Phosphatase Family EYA" contentmodel="wikitext" pagelanguage="en" touched="2018-09-27T22:33:15Z" lastrevid="4283" counter="29787" length="3012" />
      <page pageid="11" ns="0" title="Phosphatase Family LMWPTP" contentmodel="wikitext" pagelanguage="en" touched="2015-03-31T22:31:28Z" lastrevid="1901" counter="32853" length="2731" />
      <page pageid="12" ns="0" title="Phosphatase Family FCP" contentmodel="wikitext" pagelanguage="en" touched="2016-05-09T04:44:12Z" lastrevid="3706" counter="17201" length="3492" />
      <page pageid="13" ns="0" title="Phosphatase Subfamily FCP1" contentmodel="wikitext" pagelanguage="en" touched="2017-04-03T21:45:54Z" lastrevid="4150" counter="22145" length="1381" />
      <page pageid="14" ns="0" title="Phosphatase Subfamily SCP" contentmodel="wikitext" pagelanguage="en" touched="2017-03-22T01:01:01Z" lastrevid="4075" counter="11584" length="1699" />
    </pages>
  </query>
</api>