If I am reading your question correctly then you are referring to information that only a client or user might know beforehand. If there is no way to 'extract' the dynamic data from your application, in a User Path, then you will likely need JavaScript to complete this.

The simplest we have come up with is to create a 'csv' file with all the required fields and then to create the variables after you read the variable from the file or shared queue.We use the split JavaScript function to do this and then set variables in the context.

var list = "kevinl,1233456,abc123";
var MyArray = list.split(',');
context.variableManager.setValue("clientID", MyArray[0]);
context.variableManager.setValue("accountID", MyArray[1]);
context.variableManager.setValue("password", MyArray[2]);

We also output data from other scripts (into shared queues or files) in the same format to ensure we always have the data we need.

file format example:

clientid,account,password
kevinl,1233456,abc123
brucen,654321,def456