A working resource for your next decision
A famous framework becomes useful when it changes what you do on Monday. This resource pairs a link to Sam Altman’s actual Startup Playbook with original worksheets and Claude skills for testing your startup’s assumptions. You bring the company context; the pack helps turn it into a decision brief and a short list of experiments.
The original playbook was published through Y Combinator in 2015. It covers the idea, team, product and execution, with sections on topics including hiring and fundraising. Our download is an independent implementation toolkit. It does not reproduce the book, apply an official YC score, predict acceptance or claim to reveal private investment criteria.
Use it when you have a project, early customers or a pitch and want to find the next important uncertainty. It is also useful for a strategy team evaluating a new venture. You do not need to manufacture a complete business plan before starting: five honest facts and three unresolved questions are better inputs than thirty pages of confident prose.
Download YC Startup Playbook
3 skills, practical working templates and installation notes. Free, no signup.
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How to use the pack
Step 1
Write the decision you are trying to make: build an initial product, choose a customer segment, prioritise a product change or prepare for fundraising. The same company may need a different review for each decision.
Step 2
Collect evidence you already have. Customer notes, usage records, paid pilots and product demos carry different weight. The assessment skill separates observations from founder beliefs and flags where several claims rely on the same weak source.
Step 3
Choose the uncertainty that could change the decision. Design a small test with a named audience, observable result, time limit and threshold set before the test begins. A marketing activity is not an experiment until a result could make you change course.
Step 4
Close the week with a decision log. Record what happened, what surprised you, which assumption changed and what you will do next. Keep unresolved questions visible rather than replacing them with a polished narrative.
What each skill does
Start with the skill that matches the immediate job. Every skill includes its own working templates, so you can use it independently without installing the whole collection.
Startup evidence review
Use when: a new venture needs an honest assessment before the next decision
Output: A sourced decision brief with the three most consequential evidence gaps
Experiment design
Use when: a startup assumption needs a concrete customer or product test
Output: A test brief with audience, budget, evidence threshold and stop rule
Founder weekly review
Use when: a founder wants to convert the week’s evidence into a focused next week
Output: A decision log, one priority and an owned seven-day plan
Bring evidence, then ask a specific question
- A one-paragraph company description and the decision you want to make
- Customer notes, product or usage evidence, with dates and permission to use it
- Your current constraints: time, budget, team capacity and runway
The quality of the result depends on the inputs. Keep confidential or personal information out unless it is needed and you have permission to use it. If you only have a short brief, start there and let missing evidence remain visible.
A first request to try
Use the startup-evidence-review skill on this company brief and customer evidence. Separate facts, assumptions and unknowns. Select the three most consequential gaps, then use experiment-design to propose one test I can finish next week. Do not invent traction or score my chance of getting into YC.
After the first run, check the output against the underlying files. Correct misunderstood definitions and assumptions, then ask for a revision. Save the evidence ledger with the result so that someone else can inspect the reasoning later.
Upload individual skills to Claude
Choose a skill below and download its ZIP. In Claude, open Customize → Skills, choose Create skill and then Upload a skill. Select the individual ZIP and enable it. Keep the complete collection for reading or local installation.
Open Claude Skills · Official upload instructions
Each download contains one skill folder with its supporting files. Upload happens in your Claude account; this page does not install anything automatically. Availability follows your account and workspace settings.
Sources and scope
Independent and unaffiliated. The methods, prompts and checklists on this page are built on publicly documented approaches. They are not created by, endorsed by, or affiliated with any product, platform or company whose name appears here, and Tau AI has no relationship with those companies beyond using their published guidance.
- The worksheets and skills are Tau’s original work, not official YC material or an endorsement. Read the original playbook alongside them.
- A review can organise evidence and reveal assumptions. It cannot establish customer demand, founder quality or investment merit without real-world evidence.
Source pages and installation guidance were reviewed for this release. Facts about firms, products and financing can change; each research run should preserve its own access dates and recheck the evidence needed for its decision.
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Keep the complete resource
Download all skills and templates, then use one workflow at a time.
Andrew Persh
Founder, Tau AI