Business idea stress test

Challenge a business idea on customer, problem, model and economics, then get a verdict and the cheapest tests to prove or kill it.

Prompt template
Act as a skeptical but constructive investor evaluating my business idea. Your job is to find the weak points before I invest time or money.

Idea: {{idea}}
Target customer: {{customer}}
How we will make money: {{model}}
Why we think we can win: {{edge}}
Resources I have (time, money, skills): {{resources}}

Evaluate in this order:
1. **Restatement**: the idea in one sentence and the core bet it relies on.
2. **Scorecard** (1 to 5 with a one-line reason): problem severity, customer clarity, solution advantage, willingness to pay, ease of reaching customers, unit economics, defensibility, founder fit.
3. **Fatal flaws**: anything that would kill the idea, if it exists. If none, say so.
4. **Riskiest assumptions**: the 5 beliefs that must be true, ranked by how risky and how important they are.
5. **Cheapest tests**: for each of the top 3 assumptions, a test I can run in under 2 weeks for under {{test_budget}}, with a clear pass/fail threshold.
6. **Back-of-envelope economics**: price, cost, margin, customers needed to earn a living. Show the arithmetic and state the assumptions.
7. **Verdict**: Go, Pivot, or Stop, with the three reasons that matter, and one way to reshape the idea if you suggest a pivot.

Be blunt but specific. Praise only what is actually strong.
Example output
**Core bet:** small bike shops will pay a monthly fee to stop running out of fast-moving parts. | Criterion | Score | Reason | |---|---|---| | Problem severity | 3 | Stockouts hurt, but shops already have distributor accounts | | Customer clarity | 4 | Clear segment, easy to list | | Willingness to pay | 2 | Subscription plus mark-up on thin-margin parts is unproven | | Unit economics | 2 | Shipping and inventory risk eat the 10% | | Founder fit | 5 | Direct industry experience | **Fatal flaw:** none confirmed, but margin risk is serious. **Riskiest assumptions:** shops lack reliable restocking; they will pay above distributor price; you can predict demand per shop; shipping is cheap enough; owners will switch suppliers. **Cheapest tests (under $500)** 1. Call 25 shops: do at least 8 describe stockouts costing over $500 a month? 2. Offer a manual kit to 5 shops at the proposed price: 2 of 5 should pay. 3. Quote distributor lead times and compare. **Economics:** $120 + 10% on about $400 parts = $160 revenue; if parts cost $360 and shipping $15, gross profit is about $25 per month. To earn $4k a month needs about 160 shops. **Verdict: Pivot.** Charge for the service (inventory forecasting) rather than marking up parts.

Why it works

Scoring the idea against explicit criteria and demanding pass/fail thresholds for each test turns opinion into a plan. Run the cheapest test before building anything.

Licensed CC0 (public domain) Version 1 · history