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>
    <gadgets>
      <gadget id="ReferenceTooltips" desc="&lt;a href=&quot;http://www.mediawiki.org/wiki/Reference_Tooltips&quot; class=&quot;extiw&quot; title=&quot;mw:Reference Tooltips&quot;&gt;Reference Tooltips&lt;/a&gt;: Roll over any inline citation to see reference information, instead of having to jump away from the article text.">
        <metadata>
          <settings default="1" hidden="" shared="" category="浏览功能">
            <rights />
            <skins />
          </settings>
          <module>
            <scripts>
              <script>Gadget-ReferenceTooltips.js</script>
            </scripts>
            <styles>
              <style>Gadget-ReferenceTooltips.css</style>
            </styles>
            <dependencies />
            <messages />
          </module>
        </metadata>
      </gadget>
      <gadget id="GoogleTrans" desc="&lt;a href=&quot;http://en.wikipedia.org/wiki/en:User:Endo999/GoogleTrans&quot; class=&quot;extiw&quot; title=&quot;wikipedia:en:User:Endo999/GoogleTrans&quot;&gt;GoogleTrans&lt;/a&gt;: open a translation popup for the selected text or the word under the cursor when pushing the shift button.">
        <metadata>
          <settings default="" hidden="" shared="" category="浏览功能">
            <rights />
            <skins />
          </settings>
          <module>
            <scripts>
              <script>Gadget-GoogleTrans.js</script>
            </scripts>
            <styles />
            <dependencies />
            <messages />
          </module>
        </metadata>
      </gadget>
    </gadgets>
  </query>
</api>