Try it first. One prompt, checked by you.

What you need

• A computer running macOS, Linux, or Windows 10 or 11.
• A Claude account on a paid plan (Pro or higher). Claude Code does not run on the free plan. Plans and prices: claude.com/pricing. Every track on this platform needs the same plan.
• A phone on the same Wi-Fi as the computer.

1. Install Claude Code

Open a terminal. On macOS, press Cmd+Space and type Terminal. On Linux, press Ctrl+Alt+T. On Windows, open PowerShell from the Start menu.

Paste the command for your system and press Enter.

macOS or Linux:

curl -fsSL https://claude.ai/install.sh | bash

Windows (PowerShell):

irm https://claude.ai/install.ps1 | iex

When it finishes, open a new terminal window and run:

claude --version

You should see a version number followed by (Claude Code). If the terminal says claude isn't found, see Anthropic's installation troubleshooting.

2. Start Claude Code in an empty folder

mkdir klavir
cd klavir
claude

The first time, Claude Code opens your browser to log in to your Claude account. Then it asks whether you trust the files in this folder. It's empty and yours: choose yes.

3. Decide what "done" means

The client is Mojca Kranjc, who tunes and restores pianos in Ljubljana, Slovenia. Her brief is the first paragraph of the prompt below.

Before you send anything, here are the three checks you will make yourself when Claude says it's finished:

1. Phone. The page opens on your phone and reads without zooming or scrolling sideways.
2. Content. The €95 price for a standard tuning is on the page.
3. Nothing broken. The browser console shows no errors, and nothing on the page is broken: no missing images, no buttons that do nothing.

The prompt hands Claude the same three. Claude will report that it checked them. You check anyway. That is the job.

4. Send the prompt

Paste this into Claude Code and press Enter:

Build a one-page website for a client, in this folder.

The brief: Mojca Kranjc runs Klavir Kranjc, a one-person piano tuning and restoration workshop in Ljubljana, Slovenia; a standard tuning is €95, and she makes home visits Tuesday to Saturday. She wants one page a customer can read on a phone, with a button that calls her at +386 1 555 0142.

Make it a single index.html with no build step. Then serve this folder so a phone on the same Wi-Fi can open it, using something already on this computer (install nothing), and give me the exact address to type on my phone.

It is done when: (1) the page reads on a phone without zooming or sideways scrolling, (2) the €95 standard tuning price is on the page, (3) the browser console shows no errors and nothing on the page is broken. Check each one yourself and tell me how you checked.

It usually takes one to three minutes. If Claude asks permission to create a file or run a command, read what it wants to do, then allow it. If your computer asks whether to let a program accept network connections, allow it on private networks: that is how your phone reaches the page.

When it's done, Claude gives you an address like http://192.168.1.23:8000 and says how it checked each of the three.

5. Check the three

1. Phone. Type the address into your phone's browser. Scroll the whole page. If the phone can't open it, ask Claude: My phone can't open the page. What's blocking it? Guest and office Wi-Fi often stop devices from seeing each other. If it still won't open, open the address on your computer and drag the browser window as narrow as a phone.
2. Content. Find €95 on the page.
3. Nothing broken. Open the same address on your computer in Chrome, Edge, or Firefox. Press F12 (on a Mac, Cmd+Option+I) and choose the Console tab. Red lines are errors. Then tap the call button on your phone: it should offer to call the number in the brief.

If a check fails, tell Claude which one and exactly what you saw. That is pushing back too.

6. Push back once

Mojca has looked at it. Send her feedback:

Mojca opened it on her phone. She wants the call button to stay on screen while a customer scrolls. Change only that, keep the three checks passing, and tell me what you changed.

Reload the page on your phone and scroll. Does the button stay on screen? Is everything else, €95 included, as it was?

When you're done, ask Claude to Stop the server you started., then type /exit.

That loop is the platform

You decided what done meant, directed the work, checked it against what you asked for, and pushed back. That loop (direct, verify, push back) is the whole platform. Every project runs it, for a different client, on harder terrain.

Setup makes it durable: a GitHub account, a proper working folder, and the tools each track uses. On Windows, Setup moves you into WSL, a Linux terminal inside Windows, and you install Claude Code there once more.