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>
    <allimages gaicontinue="許盈宜藝術包.gif" />
  </query-continue>
  <query>
    <pages>
      <page pageid="143" ns="6" title="File:20141225C01.gif" />
      <page pageid="141" ns="6" title="File:20141225C01.jpg" />
      <page pageid="144" ns="6" title="File:20141225D01.gif" />
      <page pageid="142" ns="6" title="File:20141225D01.jpg" />
      <page pageid="17" ns="6" title="File:Chinaa02.gif" />
      <page pageid="18" ns="6" title="File:Chinaa11.gif" />
      <page pageid="139" ns="6" title="File:台灣室內設計裝修.jpg" />
      <page pageid="138" ns="6" title="File:台灣室內設計裝修2.gif" />
      <page pageid="137" ns="6" title="File:台灣室內設計裝修2.jpg" />
      <page pageid="146" ns="6" title="File:商情百科20150702.gif" />
    </pages>
  </query>
</api>