I sincerely hope that prompters consider them as guidelines - or I'm about to seriously annoy one of my prompters!

Though in practice, even if you keep exactly to the requirements of a 1000 word 'prompt' the chances that you'll come anywhere near what the prompter was actually expecting are very remote.

I've lost count of the times I've seen (and given) feedback along the lines of 'different from what I expected - but better'.