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>
    <pages>
      <page pageid="1" ns="0" title="Main Page">
        <revisions>
          <rev user="Redirect fixer" comment="[[Harp Music]] has been moved, it is now a redirect to [[Harp Music of the 18th and 19th Centuries]]" />
        </revisions>
      </page>
    </pages>
    <general mainpage="Main Page" base="http://music.lib.byu.edu/harpwiki/index.php/Main_Page" sitename="Harp Music from the 18th and 19th Centuries" logo="http://music.lib.byu.edu/harpwiki/HarpIcon.png" generator="MediaWiki 1.23.2" phpversion="5.4.16" phpsapi="apache2handler" dbtype="mysql" dbversion="5.5.56-MariaDB" imagewhitelistenabled="" langconversion="" titleconversion="" linkprefixcharset="" linkprefix="" linktrail="/^([a-z]+)(.*)$/sD" case="first-letter" lang="en" fallback8bitEncoding="windows-1252" readonly="" readonlyreason="&lt;br/&gt;&lt;span style=&quot;color:red&quot;&gt;&#039;&#039;&#039;AN UPGRADE IS IN PROGRESS.  You can VIEW, but not edit, articles and pages while the upgrade is happening.  Thanks for your patience. -David Brownell&#039;&#039;&#039;&lt;/span&gt;" writeapi="" timezone="America/Denver" timeoffset="-360" articlepath="/harpwiki/index.php/$1" scriptpath="/harpwiki" script="/harpwiki/index.php" server="http://music.lib.byu.edu" wikiid="harpwikidb" time="2017-10-18T02:02:55Z" maxuploadsize="104857600" favicon="http://music.lib.byu.edu/favicon.ico">
      <fallback />
      <thumblimits>
        <limit>120</limit>
        <limit>150</limit>
        <limit>180</limit>
        <limit>200</limit>
        <limit>250</limit>
        <limit>300</limit>
      </thumblimits>
      <imagelimits>
        <limit width="320" height="240" />
        <limit width="640" height="480" />
        <limit width="800" height="600" />
        <limit width="1024" height="768" />
        <limit width="1280" height="1024" />
      </imagelimits>
    </general>
  </query>
</api>