An AI agent pulled a penny out of my wallet and bought something with it. I didn’t type a credit card. I didn’t click a checkout button. I didn’t approve a purchase in a popup. It just paid.
The thing it bought was a fortune cookie. A fake one, procedurally generated, worth exactly $0.01. The demo is silly on purpose. The infrastructure underneath it is not.
What I built
It’s called Agent Fortune Cookie. The site is a website, technically, but humans can’t buy anything on it. There’s no checkout page. No Stripe form. No “sign in with Google.” The only customer it accepts is an AI agent.
Here’s the whole user flow:
You paste one line into your Claude: “Read https://agent-fortune.vercel.app/skill.md and help me get a fortune cookie.”
The agent reads the instructions, finds a Tempo wallet on your machine, and calls the paid endpoint.
A fortune comes back. Your agent’s name goes on a public wall next to it, with a sequence number. You were agent #437.
How it works
When the agent hits GET /api/fortune, the server responds with 402 Payment Required. That status code has been sitting in the HTTP spec since 1997, reserved for a future that never arrived. The comment on it, for decades, was basically “we’ll figure this out later.”
The 402 response carries a payment quote: how much, what currency, which address. The agent’s Tempo wallet signs a transaction, sends it, and retries the original request. The server sees the payment cleared and returns the fortune. All of this happens inside one HTTP round-trip, as far as the agent’s code is concerned. No redirect. No form. No session.
This is the Machine Payment Protocol or MPP. Tempo runs the rails. The important part is that the HTTP request itself is the transaction. There is no separate checkout layer because there doesn’t need to be one.
Why this matters
Credit cards were designed for humans holding plastic. API keys, which is how software pays for software today, aren’t really payments. They’re pre-paid subscriptions with a bunch of account management bolted on. You sign up, you pick a plan, you enter a card, you get a key, you make requests against a bucket until the bucket runs out.
That model breaks the moment your customer is an agent.
An agent doesn’t have an email address. It doesn’t want to pick a plan. It certainly doesn’t want to sign up for twelve different services to do one task. What it wants is to make a request, pay for that request, and move on. Per call. Per unit of work.
Once you can do that, the pricing shape of the internet changes. Sub-cent APIs start to make sense. A service that charges $0.002 per call was impossible before (the credit card fee alone would eat it), but it’s fine when the payment rides on the request itself. Whole categories of tiny, single-purpose services become viable. Your agent composes them on the fly. You don’t know or care which ones it used.
That’s the shift I wanted to make concrete. Not slides. Not a whitepaper. A website where an agent walks up, puts a penny down, and walks away with a cookie.
Try it
If you have Claude Code, Cursor, or Windsurf and five minutes, you can run the full flow yourself. You’ll need a Tempo wallet (the agent will walk you through creating one). The cookie costs a cent.
Let me know what fortune you get.