Subscription tiffin service for working professionals in Pune, ₹3,500/month
You get
Riskiest: people will commit to a monthly plan before tasting.
Test: a WhatsApp group in two office complexes, 20 paid trial weeks — pass if ≥ 8 convert to monthly.
Ask: 'What did you eat for lunch yesterday, and what did it cost?'
About this skill
About Idea stress test
Founders fall in love with an idea and spend months building before testing the assumption most likely to kill it. This skill lists the assumptions behind your idea — about the problem, customer, solution, channel and money — ranks them by importance and uncertainty, and designs a test for the top three that costs little and takes a week or less. It sets kill criteria in advance and suggests questions for ten customer conversations. Its job is to try to break the idea, not to validate it. To use it, paste the skill into your assistant and send your idea in a few sentences: who it's for, the problem, the solution and how it makes money.
Idea stress test — example input and the first lines it returns. Works in ChatGPT, Claude and Gemini.
2 Paste it into a new chatChatGPT, Claude, Gemini or Copilot.
3 Send your inputSend your idea in a few sentences: who it's for.
The skill — paste this into your AI assistant
# Skill: Idea stress test
You are running the "Idea stress test" skill for me. I work as: Startup founder. What I need from you: my idea's riskiest assumptions, ranked, with a one-week test for each.
## When I send you my idea in a few sentences: who it's for, the problem, the solution and how it makes money
1. List assumptions about the problem, customer, solution, channel and money.
2. Rank them by risk (importance × uncertainty).
3. Design a cheap test for the top three that takes a week or less.
4. Define what result would make you stop.
## Reply in this format
- Assumptions table: assumption, importance, uncertainty
- Top three tests (method, cost, pass/fail threshold)
- Kill criteria
- Questions to ask ten customers
## Rules
- Don't validate the idea; try to break it.
- No market-size numbers unless the user gives a source.
- Use only the facts I give you; mark anything you had to assume with [ASSUMPTION].
- If something essential is missing, ask me one short question, then continue.
- No preamble or filler: start with the result.
Confirm you're ready in one line, then wait for me to send my idea in a few sentences: who it's for, the problem, the solution and how it makes money.
Then sendYour idea in a few sentences: who it's for, the problem, the solution and how it makes money. For example: Subscription tiffin service for working professionals in Pune, ₹3,500/month
ChatGPT
Fastest: paste the skill as your first message in a new chat, then send your input.
To keep it: open a Project, choose Instructions (or Settings → Personalization → Custom instructions for every chat) and paste it there.
To share it with a team: create a custom GPT and paste the skill into its Instructions.
In the Codex app: copy the skill's folder into ~/.codex/skills/ (or Customize → Skills → Add → Create skill).
Claude
Fastest: paste the skill as your first message in a new chat, then send your input.
To keep it: create a Project, open Project instructions and paste the skill.
As a Claude Skill: download the skill's ZIP, then in Claude open Settings → Skills → Add → Upload skill and choose the file.
Gemini
Fastest: paste the skill as your first message in a new chat, then send your input.
To keep it: open Gems → New Gem, paste the skill into Instructions and save.
Microsoft Copilot
Fastest: paste the skill as your first message, then send your input.
In Microsoft 365 Copilot, save it as a prompt or paste it into an agent's instructions to reuse it.
Any other assistant
Paste the skill as the system prompt or first message in any chat assistant (Perplexity, Meta AI, DeepSeek, Mistral, local models).
Coding agents that read the Agent Skills format (SKILL.md) can load the downloaded file from their skills folder.
Install it permanently
Upload it to Claude, add it to ChatGPT's Codex app, clone it into Claude Code, or download the SKILL.md for any agent. Full guide with screenshots →
Download the ZIP and upload it in Claude. Claude then uses the skill on its own whenever a request matches.
Top three tests (method, cost, pass/fail threshold)
Kill criteria
Questions to ask ten customers
Rules it never breaks
Don't validate the idea; try to break it.
No market-size numbers unless the user gives a source.
Uses only the facts you give it and marks assumptions.
FAQs
Questions about Idea stress test
What does the Idea stress test skill do?
Founders fall in love with an idea and spend months building before testing the riskiest assumption. The skill fixes that: your idea's riskiest assumptions, ranked, with a one-week test for each.
How do I install Idea stress test in ChatGPT, Claude or Gemini?
Copy the skill and paste it as the first message of a new chat, then send your input. To keep it, paste it into a ChatGPT Project or custom GPT, a Claude Project or a Gemini Gem, or upload the SKILL.md file as a Claude Skill.
What do I send Idea stress test after installing it?
Send your idea in a few sentences: who it's for, the problem, the solution and how it makes money. If something essential is missing, the skill asks you one short question and then continues.
Is the Idea stress test skill free?
Yes. It's free to copy, use and adapt, with no sign-up, and works in the free versions of ChatGPT, Claude, Gemini and Copilot.
60 research-backed principles in 6 categories — what each one means, why it works on the human brain and how to use it on your own screens. Written by Sushant Singh, founder of Science of Apps, who has scaled consumer apps to lacs of users and spent 10+ years leading product across startups and digital businesses in the US, EU & India.
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