Build version 1 by describing it

Build-along · ~40 min at your own keyboard

Most assistants can build a small working app inside the chat. You describe it in plain words and it shows a live version beside the chat. You do not write code. Paste your spec. Look at what comes back. Then change ONE thing at a time. This matters. If you ask for five changes at once, the builder often breaks something and you cannot tell which change did it. Test after every change. If it gets worse, ask it to undo the last change. There is a second path for owners who want to go further: a coding agent that works on files on your computer. It is optional and it needs a terminal. You will find it as the Code route on this page.

Ladder · Level 5The long version: Building with AI ↗

Your starter: Build kickoff

Prompt

Make it yours: Put your own spec where the bracket is. Fill the change log as you go, one line per change, and say plainly what still does not work.

FIRST MESSAGE TO THE BUILDER
Here is a one-page spec for a small tool. Build the smallest version only.
- Make it work on a phone first.
- Use made-up sample data. No real customer details.
- Do not add anything that is not in the spec.
- If something is unclear, ask me one question before you start.
- When it is ready, tell me how to try each of my three done checks.

[your spec, all six parts]

CHANGE LOG (one change per message)
1. Asked for:
   Result: worked or undone
2. Asked for:
   Result: worked or undone
3. Asked for:
   Result: worked or undone

DONE CHECKS
1. Pass or fail:
2. Pass or fail:
3. Pass or fail:

STILL DOES NOT WORK
-

The coach checks that what you paste back is your own work. The starter pasted back unchanged won't pass.

Do this

0/7

Checkpoints

▸You should now see a live version 1 of your tool, with sample data, next to or after your spec.
▸You should now see a written pass or fail for each of your three done checks.
▸You should now see a list of changes, one per line, each marked worked or undone.

The three ways this goes wrong

The builder made a big app with features you did not ask for. — Say: 'Remove everything that is not in the spec. Keep only the one job.' Then use the spec's smallest-version section as your first message next time.
A change broke something that worked before. — Say 'Undo the last change.' Then ask for a smaller version of the same change. Ask for one change at a time from now on.
The builder produces a pretty app that does nothing, or loses your data when you reload. — Ask it: 'Make the buttons work with real saving, not just a picture.' If it cannot save data, that is expected in a chat builder. The next lesson puts your data in a real table.

Dated facts in this lesson: ChatGPT has Canvas for building in chat. Codex is available in every ChatGPT tier including Free, and Plus adds the CLI, IDE and web versions. The CLI installs with npm i -g @openai/codex (researched Oct 4, 2026, not yet confirmed by a person: check the source before you rely on it); Claude Code needs Pro or above. Mac and Linux install with: curl -fsSL https://claude.ai/install.sh | bash. Windows installs with: irm https://claude.ai/install.ps1 | iex (researched Oct 4, 2026, not yet confirmed by a person: check the source before you rely on it); Gemini has Canvas. The Jules coding agent has a free tier of 15 tasks a day. Gemini CLI free users moved to Antigravity CLI on June 18, 2026 (researched Oct 4, 2026, not yet confirmed by a person: check the source before you rely on it); Microsoft 365 Copilot has Agent Builder and Pages. GitHub Copilot has a free tier and paid plans (researched Oct 4, 2026, not yet confirmed by a person: check the source before you rely on it); Perplexity Labs allows 50 runs a month on Pro (researched Oct 4, 2026, not yet confirmed by a person: check the source before you rely on it).

Share what happened

Paste: your first message to the builder, a list of your changes (one line each, marked worked or undone), your pass or fail for each done check, and what still does not work. Add a link or screenshot description if you can.

Strip API keys, passwords, and tokens before you paste. Swap them for [KEY].

🔒 Don't paste confidential, personal-health, or payment info.