AI Agents Can Now Pay for Things: Inside the New 'Agentic Commerce' Protocols

For most of the past few years, "AI agent" meant something that could research, draft, or click around a website on your behalf, then hand the last step — entering a card number, hitting "place order" — back to you. That last step is now getting automated too. Over the past year, Visa, Mastercard, Google, OpenAI, and Stripe have each shipped a real, working protocol for letting an AI agent complete a purchase directly, and the approaches differ enough to be worth understanding before you let a chatbot near your payment method.

What's live right now

The most concrete example is inside ChatGPT. OpenAI and Stripe built Instant Checkout, letting US ChatGPT users buy directly from Etsy sellers in the chat window, with a large number of Shopify merchants (Stripe named Glossier, SKIMS, Spanx, and Vuori) rolling out too. It runs on the Agentic Commerce Protocol (ACP), which OpenAI and Stripe published openly so other merchants and platforms can adopt it. The pitch to merchants is a small integration change if they already use Stripe; the pitch to shoppers is that the price isn't marked up and product recommendations aren't influenced by who's paying for placement, per OpenAI's own announcement.

That's one working implementation, but it isn't the only standard in play, which is exactly where this gets more complicated.

The card networks built their own verification layers

Visa and Mastercard, whose business is verifying and settling payments rather than building chat interfaces, each shipped something different: a way for a merchant to confirm that an incoming request genuinely comes from an authorized agent acting for a real customer, rather than a scraper or a bad actor pretending to be one.

Visa's version, the Trusted Agent Protocol, built with Cloudflare, attaches a cryptographically signed identity to the agent's web requests. A merchant's server checks that signature against a Visa-run directory and treats the request as coming from a known, accountable agent instead of an anonymous bot — which matters given retailers have reported enormous increases in AI-driven traffic, much of it from crawlers and agents with no way to verify who they were.

Mastercard's Agent Pay, announced with Microsoft and IBM as early partners, applies a similar goal to the token itself: an "Agentic Token" scoped to one agent, one merchant, and one consent policy, so an agent completes a checkout without ever handling the actual card number. Mastercard has since extended this with Agent Pay for Machines, aimed at agent-to-agent payments — one AI system paying another for API usage or data, potentially in fractions of a cent.

Google's approach: an open standard, not a network

Rather than building on its own payment rails, Google published AP2 (Agent Payments Protocol) as an open spec other companies can build on, getting dozens of partners — including PayPal, Mastercard, American Express, and Coinbase — to sign on at launch. AP2's core idea is a pair of signed digital records: an "Intent Mandate" capturing what you asked the agent to do, and a "Cart Mandate" capturing the specific purchase it's proposing, both cryptographically tied back to you — so if an agent buys the wrong thing, there's a verifiable record of what it was authorized to do versus what it actually did. Google later handed governance to the FIDO Alliance, the body that manages passkey standards, suggesting it wants AP2 to become shared infrastructure rather than a Google product.

Why this fragmentation is normal, and mostly fine, for now

Having Visa, Mastercard, Google, and OpenAI each ship something different sounds chaotic, but it maps onto a familiar pattern: card networks build verification and settlement, platforms build the shopping experience, and an open protocol standardizes what everyone needs (proof of consent, a clear record of what was authorized). Several efforts are explicitly designed to interoperate rather than compete — Mastercard has said its framework works alongside AP2 and similar protocols, not against them.

What actually matters if you try this

The useful question isn't "which protocol is best" — you won't get to choose that, the merchant and platform decide it for you. The useful question is what you're actually authorizing: does a purchase require your confirmation before completing, is the amount and merchant scoped in advance rather than open-ended, and can you revoke the agent's access without canceling your entire card. Every protocol here was designed with scoped, revocable permission rather than unlimited discretion — but "designed with" and "implemented carefully by every merchant" aren't the same guarantee. Treat an AI shopping agent like a very literal-minded assistant: fine for a specific, bounded task you've described clearly, worth watching closely the first several times before trusting it with anything you'd be annoyed to get wrong.