Q1 Demand realityWhat's the strongest evidence you have that someone actually wants this?Q2 Status quoWhat are your users doing right now to solve this problem, even badly?Q3 Desperate specificityName the actual human who needs this most.Q4 Narrowest wedgeWhat's the smallest possible version of this that someone would pay real money for?Q5 ObservationHave you actually sat down and watched someone use this without helping them?Q6 Future-fitIn 3 years, does your product become more essential or less?✓ Then: premise challenge, alternatives, a design doc. No code.
A startup idea in one sentence
Test demand, the status quo and the smallest version before anything is built
Phase 2A of Garry Tan's office-hours skill
The answers are yours. The skill asks the questions and pushes back; it cannot know your market for you.
Answer with evidence, not intentions. If an answer is weak, go and observe a real user before building.