This info is in the design Mappings SP3 guide.
Runtime Constants
In the same way as in Java mappings, the mapping runtime in XSLT programs also returns
parameters that you can use to evaluate information in the XSLT program that is not known
until runtime.
Constants Provided by Mapping Runtime
Constants Meaning
$SenderSystem Sender business system name
$ReceiverSystem Receiver business system name
$Direction Message direction. This parameter is only relevant for XSLT
message mappings; where only the strings Request, Response and
Fault are permitted as values.
$SenderName Sender interface name
$SenderNamespace Sender interface namespace
$ReceiverName Receiver interface name
$ReceiverNamespace Receiver interface namespace
If you want to access one of the constants in the XSLT program, you first have to declare the
constant as a parameter, for example:
<xsl:param name="SenderSystem" />
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