Get Sheet Count per documentSet from REST API

OL Connect Enterprise Workflow
1

I am working with the REST API.
My job preset has the following levels:

  • Job segments group documents sets which have the same number of sheet range and which need to go into different envelope size: c65 (1-5 sheets), c4 (6-18 sheet)…etc

  • Document sets group the invoices belonging to the same clients.
    In the output preset the sheet count per set is available through ${set.count.sheets}.

I am writing a REST API script in Workflow after the Create Job task and I need to know the URI of the entity service which retrieves the sheet count per document set. If there isn’t one, is there any way to compute this value (i.e number of sheets per documentSet) using other entity services?

My Output is AFP.