So for example:
/cmdstart vanilla
>Pudding
>IceCream
>Beans
/cmdend
???
Lets say you want to enter a bank, deposit money, specify an amount, and walk away. Either of these is how I'd suggest doing it:
>/cmdmode
>bank
>deposit
>500
/cmdmode
or
>/cmdmode
>bank, desposit, 500
>/cmdmode
Where each line is a new text session. Each field - "bank", "deposit", "500" - is defined by the eventer using the same set-up as the current command events. Pertaining to the two above methods of input, the former would be used by someone who is new to the server and doesn't know all of the commands, and the latter is for players that know the commands and can easily type it all out quickly. The only difference between these command events and using an event system that utilizes OnPlayerTalk is that these have a defined functional range and any text the player types does not show up for the entire server to see. This system allows interaction with systems to be more fluid and natural.