This page is designed to provide developers with a space in which they can provide feedback to their peers on the challenges they have faced and overcome in writing proxy tools. Please add your advice to the page so that lessons can be learned by all. Of course, please also correct or expand on any misconceptions you find reported here.
Simple XML Response Proxy Server Pages are not so simple!
According to the documentation, touch-points (actions) such as Ping expect a response in the form of "a simple XML response instead of a resulting HTML page". However, a closer look at the documentation shows that the response is not XML at all but instead the word SUCCESS or ERROR surrounded by <result> tags. For example,
<result>SUCCESS<result>
Notice that there is no closing result tag (</result>) as one might expect if this were actually XML!