A deliberately narrow build that answers one question — can it be done, will they use it, does it perform — before you fund the rest.
Four areas where this work is won or lost.
The hard part of the idea built in isolation, so the risk is retired before the budget is committed.
Something real enough for people to react to, in front of the audience that would pay.
A thin end-to-end slice through the systems that are most likely to surprise you.
A short write-up of what was learned and what it means for the full build.
A short loop with a written result at every step.
One falsifiable question and the result that would count as a yes or a no.
Only what is needed to answer it, with shortcuts labelled so they are not mistaken for the product.
What it proved, what it did not, and the recommended next step.
Chosen for your product, not for our habit.
Name it. We will scope the smallest build that can show whether it holds.