Your brief
I give individual online lessons. Two customers pay per lesson and came through acquaintances. I want to offer a subscription. I have ten teaching hours a week and do not yet know how much time support between lessons takes.
Possible draft
Fictional example: an online language tutor
KNOWN: two paying customers and ten available teaching hours. ASSUMPTION: customers want a subscription. Open question: time and cost of support between lessons. The consistency check asks whether the promised contact fits the available hours and price.
