Agent determination best practices

Question

Hi, workflow dev team!
Another question about workflow best practices.
I build a workflow, the first step of each workflow, at least as I see it, is to determine agents for all steps in the workflow and store it in multiline WF-container. After that, to use this WF-container data to execute a step inside of workflow.
The questions are:
1. Suppose, I filled a WF-container with a list of all possible agents and their position (in order to supply more user-friendly approve/decline notifications) for the different steps inside of this workflow (username & position). As I understand, I can access to specific line of multiline container with &AGENTS[&INDEX&]& inside of EXPRESSION field (not via ABAP-code in method of class), but how can I access specific column of the WF-container? E.g. &AGENTS[1]& will return «USJOHN — Junior Manager», is it possible to retrieve username and position from multi line and pass it to the task as two separate container elements?
2. Is it possible to query specific line of multiline container element according to some logical condition inside of EXPRESSION field (not via ABAP-code in method of class) or in order to do this I have to implement that logic inside of ABAP class method?
And the last question, probably, less connected to the questions asked above.
3. If I need to define agents for the task, what is the best approach to do that:
— define the task as General Task and insert the relevant agents as multiline container element via EXPRESSION field;
— to play with Agent Assignment (try to implement agent determination logic there) and not to define the task as general one.
Thanks.

Answer 1

Ronen already had great input, but here are some additional points:
-In general I would try to avoid some kind of "Let's get all the agents at the beginning of the workflow into a multiline container, and try to pick up the correct ones for the individual steps" approach. Of course if your aim is just to display the list of agents somewhere (task description etc.,), then this might be OK approach.
-Rules are better than expressions in agent determination (at least in most cases). If the approvers change during the process, you can (as an WF admin) just click the "Execute agent rule again" functionality, and the system will find the correct new approver for the work item. Otherwise you need to go to manipulate the container element(s) (and first figure out that who is the approver).
Answer for 3: You don't need to use only expressions/container elements. Try to check if you can use rules. In some rare cases you might consider of using the tasks' agent assignment (the same place where you set the task as general task). Let's say that you want to send the work item to all users that have certain authorization role. Now you can set the role as a "restricting entity" at the task level (=same place where you set the general task). This will mean that only the users who have the role are the possible agents for the task. And now if you leave the agent determination part at the workflow template empty (no expressions, no rules etc), you are done!
Regards,
Karri