I have played the stock game for awhile, and I think to remember that you precisely get a message if the enemy detects you, just after sending his alert message. But too much time has passed , so I'm not sure anymore.
If it exists in the stock game, then chances are that a MOD can be made for it, e.g. an optional mod for TWoS.
@bstanko6,
that's very instructive, thanks to post this here
