You supply functions, not tasks
Although the main interaction performed by end users in the Botize site is the creation and configuration of tasks, you as the application developer must be concerned about functions only.
Your job is to develop triggers that generate data and actions that receive data, that's all. How these functions are combined by end users to create tasks is something that you do not need to care about, and in fact, you have no means to know how your functions are being “glued” together by end users to form tasks. So, in short: when developing a Botize application, just concentrate on developing self-contained functions that communicate with the outside world via input and output data and that can be tested in isolation.