Your app idea →
a tiny plan + your first 3 prompts
One sentence in. What to build, what to skip, and three ready-to-paste prompts in build order. Free, no sign-up.
Free · no sign-up · your idea isn't stored · See 5 real examples →
How it works
- Describe your app idea in one sentence. Plain words are fine, e.g. "a site where my D&D group tracks loot".
- Pick the tool you build in. Cursor, Lovable, Bolt, Replit or ChatGPT.
- Get a tiny v1 plan: what to include, what to skip (and why), the simplest stack and the main screens.
- Paste three prompts in order. Paste prompt 1, check it works, then prompt 2, then prompt 3.
Prompts tuned to your AI builder
- Cursor: scaffolds a small local project (e.g. Vite + React) and tells you how to run it.
- Lovable: describes screens and behaviour; Lovable handles setup and publishing.
- Bolt: keeps everything in the browser so it runs and deploys with no configuration.
- Replit: uses Replit's built-in server and database when the app needs a backend.
- ChatGPT: a single index.html you can open by double-clicking, nothing to install.
Why scope v1 first
The most common way vibecoding projects stall is asking for everything at once: accounts, payments, sharing and an admin panel in the first prompt. The AI tries to build it all, and you end up debugging a big half-working app.
FirstThree does the cutting for you. It picks the one thing your app must do, lists what to leave out for now, and splits the build into three small steps that each end with something you can click and test. Once v1 works and you've used it, adding the next feature is much easier.
FAQ
What is FirstThree?
FirstThree is a free web tool that turns a one-sentence app idea into a tiny v1 build plan (what to include, what to skip, the simplest stack and the main screens) plus exactly three copy-paste prompts, in build order, for your AI coding tool.
Which AI coding tools does it support?
Cursor, Lovable, Bolt, Replit and ChatGPT. The plan and prompts are tuned to the tool you pick, for example a single-file setup for ChatGPT or Replit's built-in server and database for Replit.
Is it free? Do I need an account?
Yes, it's free and there's no sign-up. To keep it free there are fair-use limits per person and a daily cap on total plans.
Why only three prompts?
Three small prompts are enough to get a working first version: set up the core screen, make the main feature real, then polish. Pasting one big prompt usually produces a tangle of half-working features that's hard to fix.
Can I write the first prompt myself?
Yes. Our first-prompt guide has a copy-paste template, the 3-prompt build order and the most common mistakes. FirstThree just does it for you from one sentence.
How do I plan an app before I prompt ChatGPT?
Keep v1 to a single index.html file you can open with a double-click, and split the build into three prompts (core screen, saved data, polish). Our ChatGPT planning guide has a copy-paste template, a real example and the usual mistakes. Or type one sentence above and we'll write the three prompts for you.
What should I do after the three prompts?
Use the app yourself for a few days. Then pick the next thing you actually missed and ask your tool for just that, one feature per prompt.
Do you store my idea?
No. Your idea is sent to the AI model to generate the plan and isn't saved by FirstThree. The site keeps only anonymous daily counts (page views and number of plans), with no IP addresses or idea text. If you join the newsletter, your email address is kept by our email provider, Resend, until you unsubscribe. See the privacy page for details.