Snehal,
manpower supply refers to amount claimed with reference to wages sheet only,
as we aware that no laborers are directly engaged by any establishment, companies are giving it as sub contract,
you refer your condition sheet is it is for manpower supply then service tax will be applicable
else department will refer this as business auxiliary service and they demand service tax from your sub contractor,
important aspect is that your contractor is routed through proper work order, and instead of manpower supply, piece rate contract will not attract service tax,
The value of work done by job worker inside the factory premises is ultimately attract addition of cost in finished goods and there excise duty will be discharged by the manufacturer,
however notification 25/2015 says that service tax is applicable where no excise duty paid on final product, in case you made supply to some exempted projects where ED is exempt by virtue of any notification then service tax issue will arise, so far there is no clarity on this.