Sam Altman wrote a free startup bible. Here's how to turn it into a brutally honest cofounder that pressure-tests your idea and tells you exactly where you're weak, before you waste a year.
Sam Altman, the guy who runs OpenAI, wrote a free guide called the Startup Playbook. It's basically everything they teach founders at Y Combinator, the startup accelerator behind Airbnb, Dropbox, and Stripe. And it's all in one free guide.
The problem? Most people read it once and forget all of it. So here's what I'd do instead: let AI hold your idea up against it and tell you the truth.
Open Claude or ChatGPT and give it three things:
1. The playbook. Go to playbook.samaltman.com, copy the text, and paste it in (or drop in the link).
2. The prompt below. This is what turns the AI into the brutally honest cofounder.
3. Your business idea or side hustle. A paragraph is plenty, what it is, who it's for, and how it makes money.
From there, it pressure-tests your idea against the playbook and tells you where you're weak and what to do first.
Paste this in right after the playbook and your idea:
The prompt
You are a brutally honest startup cofounder who has internalized Sam Altman's Startup Playbook (pasted above). I'm going to give you my business idea. Do not be nice. Be useful. Pressure-test my idea against the playbook across these five areas: 1. THE IDEA, is it actually solving a real, painful problem people want solved? Is the market big or fast-growing enough? 2. THE PRODUCT, would people genuinely love this, or just kind of like it? What's the "so good people tell their friends" version? 3. THE TEAM / ME, do I have an unfair advantage here, or am I easily copied? 4. THE EXECUTION, what is the single most important thing I should do in the next 30 days, and what am I likely to waste time on instead? 5. THE MARKET / TIMING, why now? What has changed that makes this the right moment? Altman says 99% of startups die from suicide, not murder, meaning they kill themselves with their own mistakes, not the competition. So tell me: what is the most likely way I quietly kill this myself? Be specific. Format your answer as: - A blunt grade out of 10 for each of the five areas, with one line of why. - My three biggest weaknesses, ranked. - The one thing I should do first. Ask me one clarifying question if you need it before you start.
The Real Win
Altman's most famous line is that 99% of startups die from suicide, not murder. It's almost never the competition, it's you. The whole point of this is to let AI be the honest cofounder who catches that quiet self-sabotage before you sink a year into the wrong thing.
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