Visa AI Passport

A prototype of how an AI agent could pay on your behalf: a risk check, a one-use token and a stop button for every purchase.

Abstract

When an AI agent shops for you, someone has to decide whether it may pay. The AI Passport is a connector between any chat agent and the card network. The agent asks the passport before every purchase, the passport scores the risk, and only low-risk purchases go through without you. Anything else comes back to you for a yes or a no.

I built the working prototype in two days during the LSE sprint week, on a brief set by Visa, and made the film that explains it. A real language model runs the conversation, so visitors can ask for anything, by voice or text. Payments are simulated.

Technical overview

Agent: Claude Haiku with four tools: search offers, passport check, passport pay, passport status.
Risk: Each purchase is scored 0 to 100. At 40 or above the user approves once or declines.
Payment: A one-use token per purchase, never the card number. Stop still works for four seconds after settlement.
Interface: One chat shell that can dress as four different assistants, to show the passport travels with the user.
Stack: TypeScript on Cloud Run, 184 tests, usage caps per visitor and per day.

Laptop mockup: the payment card inside the chat — The payment card inside the chat: each check ticks off before the one-use token is spent.

The passport, its limits and a one-time token — What the user sets once: who the agent is, what it may buy and up to what amount.

Laptop and phone: the bank confirms the payment — After settlement the bank confirms on the phone.

One purchase, end to end. The agent never holds the card: it asks, the passport decides.

Class prototype from the LSE sprint week. Not an official Visa product.