How to get stored procedure parameters details?

Question

Where can I find information about stored procedure parameters? In my situation I need to know only the input parameters of given store procedure.

In the sys.o

Answer 1

select  
   'Parameter_name' = name,  
   'Type'   = type_name(user_type_id),  
   'Length'   = max_length,  
   'Prec'   = case when type_name(system_type_id) = 'uniqueidentifier' 
              then precision  
              else OdbcPrec(system_type_id, max_length, precision) end,  
   'Scale'   = OdbcScale(system_type_id, scale),  
   'Param_order'  = parameter_id,  
   'Collation'   = convert(sysname, 
                   case when system_type_id in (35, 99, 167, 175, 231, 239)  
                   then ServerProperty('collation') end)  

  from sys.parameters where object_id = object_id('MySchema.MyProcedure')