Only those variables that are within the current scope are passed to a service that you invoke in a DSP. So, to ensure that a service receives all the variables it needs at run time, you must make sure that all those variables are within the scope. For more information about passing parameters to and within a DSP, see Passing Parameters with a DSP.

Only those variables that are within scope can be addressed without qualifiers. (See Referencing Variables In and Out of Scope.) Moreover, except for the initial scope (whose variables exist for the entire life of a DSP), certain tags, such as the %end% tag, cause the current scope to close and discard the variables within it.