So, I made a smart-assed prompt. But really the conventional prompt would be "The answer is a so-and-so many letter word" and what does it matter how many letters it has? It has 10 if that matters.
The mechanism is simple and I'd find it hard to believe if it hasn't been done before. Still the mechanics of actually doing it might be a little hard to actually do.
It is not an intuitive meta and is one where the answer is spelled out. A submitted wrong answer has been "riverrun". I like the way you think but, you have to do more than just that.
Heres a starter nudge: If the end is just the beginning, what is the penultimate? and a second: (try not to need this one)The last shall be first.... well, one of the last shall be first. The other last will just be last.