Are you executing the script against servers?
If so, you can set the parameter to be a server property, then create a property of enumerated datatype.
You'll need to create a new property under the built-in server class, and then set the default value of the NSH script parameter to this property.
In this manner, when you select a target server to execute the script against, the value of the script property will change according to the value on the specific target server.
For example, setting the NSH script parameter to be the operating system version of the target server:
We do use server properties for some frequently used jobs as described, but can't really define new server properties for every application we use (the number of server properties we have now is getting out of hand).
If we can't enumerate script parameters we'll just have to do errorchecking within scripts.