Attention, plug-in code developers.
I'm adding plug-in support for the new, upcoming contest types. Basically, they'll announce winners on a known channel in a known format. However, I'm not sure how best to support your security desires.
The key is to making your plug-in listen only to the authorized board, to avoid spoofing. For the contest board, this is done by giving it the ability to announce any text the user wants to announce on a known channel, so you can be sure it's the right board.
This time around, I'm thinking what it'll do is when the owner clicks on the board, it announces itself. That way, the timing is the control factor, not the message; if your plug-in listens briefly on the channel, odds are low someone will spoof in that brief setup time.
Would this meet your needs? Or would you prefer something completely different?