What Parameter Syntax are available on RSSP?

Summary:

We want to know what Parameter Syntax are available on RSSP?

Content (please ensure you mask any confidential information):

We utilize Parameter Syntax in the where clause of a table validate LOV and assign it to the REQ Line DFF in Classic SSP.

During RSSP validation, we find a Parameter Syntax :{PARAMETER.RequisitioningBUId} is not working in the RSSP view requisitin line page.

We can enter the Req Line DFF value in the edit requisition line page but system does not show the dff value in the RSSP view requisitin line page.

We are about to log SR for this issue, but is the list of PARAMETERs supported by RSSP published somewhere?