How to turn a messy app idea into a clear plan with AI

Short answer: paste the prompt below into your AI coding tool (Cursor, Claude Code, Replit, Lovable, Bolt or ChatGPT), fill in the [PLACEHOLDERS], and send. SI's tip: no stress, getting stuck is totally normal. You've got this. This is prompt "01. Brain Dump to Clear Idea" from the Hey SI Starter Pack.

When to use it: At the very start, when your idea is still a jumble of thoughts. Use it before you open a code editor. (Use a normal AI chat like ChatGPT or Claude, or your coding tool's chat.)

The prompt

I want to build my first app, but my idea is still messy. I'm a complete beginner at coding.

Here's my brain dump:
[WRITE EVERYTHING YOU'RE THINKING: WHAT IT DOES, WHO IT'S FOR, WHY YOU WANT IT, APPS IT'S LIKE]

Please help me get clear:
1. Rewrite my idea as ONE simple sentence: "[App] helps [who] do [what] so they can [why]."
2. Tell me who the main user is.
3. List the 3 most important things the app must do.
4. Point out anything in my brain dump that sounds big, complicated, or expensive for a beginner.
5. Ask me up to 5 questions whose answers would make the idea clearer.

Use plain, non-technical language. Don't write any code yet.

Example (filled in)

Here's my brain dump: I keep forgetting when to water my plants. Something like a to-do app but for plants. Maybe photos of each plant, reminders, maybe it knows what kind of plant it is from the photo? For me and my roommate. Kind of like Todoist but cute.

What you might get back: "PlantPal helps plant owners keep track of when each plant needs water so they stop killing their plants." It would also flag "identify the plant from a photo" as hard for a beginner.

Tips

• Write messy. Don't tidy it up first, because the AI is good at sorting.
• Answer the questions it asks, then say: "Now rewrite the one-sentence idea using my answers."
• If it flags something as hard, put it on a "later" list. Don't throw it away.
• Save the final sentence somewhere. You'll paste it into Prompt 02.

New here? Start with how to vibe code your first app and set up an AGENTS.md rules file.