Using Invoke method

what is the target type means in Invoke method?
I took a List of type String and assigned some default values to it and took a invoke method.
when i click on the parameters and pass one parameter i dont see any error. and it runs successful and i am able to see string data in output panel.
when i am trying to enter multiple parameters i am getting error, PFA screenshot.

Hi @ramyat,
I hope this topic will help you: