he AIF framework is able to communicate with XML messages to the outer world. However there is a small limitation. The format of this XML message should sometimes be altered for this outside world. Microsoft BizTalk can be a solution, when messages are send to different parties and every party has his own XML layout, but when this message has to be send to just one party XSLT can help you out.
XSLT is a mechanism that can rebuild an XML message to a different format (XML to XML or XML to xHTML).
It is possible in AX to use XSLT (BASIC\SETUP\AIF\XSLT Repository. You can use these XSLT in the Endpoint Actions Pipeline Components. The XSLT in AX can only transform the body node of the XML message.
You can test the default AX XML and your XSLT in AX using form tutorial_XSL