In the first post of this series we said the AI front door is open. This post is the map of what is on the other side. The change since 2025 is that the big AI assistants stopped only talking about products and started selling them, and the card networks built rails so an agent can pay. For a merchant the practical question becomes concrete: which aisles are these, who controls each one, and where do you still own the customer?
The discovery surfaces: where AI buyers show up
These are the places a shopper (or the agent acting for them) asks "what should I buy?" and increasingly gets a buy button next to the answer. Four matter most today. All launched their commerce features in the US first, so availability outside the US still lags.
ChatGPT: the biggest audience, a checkout in flux
ChatGPT was first to put a real cart inside the chat. On September 29, 2025, OpenAI and Stripe launched Instant Checkout, letting US shoppers buy from Etsy sellers, with over a million Shopify merchants billed as coming soon, without leaving the conversation. It runs on the Agentic Commerce Protocol (ACP), an open standard Stripe and OpenAI built together.
Then the honest update. In March 2026, OpenAI scaled native checkout back. Very few merchants had integrated it, and shoppers tended to finish on sites where their payment and account details already lived, so OpenAI refocused ChatGPT on product discovery and comparison and pushed the actual checkout back to merchant-controlled paths. (A widely cited roughly 4 percent platform fee on Instant Checkout sales was reported by The Information, citing Shopify, not published by OpenAI.)
For a merchant: the takeaway is steadier than the headlines. Be discoverable and buyable in ChatGPT, but expect the final transaction to land on your own checkout more often than not.
Google AI Mode and Gemini: the deepest catalog
On November 13, 2025, Google rolled out agentic checkout across AI Mode and the Gemini app in the US. It is backed by the Shopping Graph, more than 50 billion product listings with around 2 billion refreshed every hour, so Google's view of price and availability is unusually fresh. The agent can watch a product and buy it when the price drops to your budget, with the shopper confirming first. Early checkout partners included Wayfair, Chewy, Quince, and select Shopify merchants.
Google's standard here is the Universal Commerce Protocol (UCP), its own open spec for connecting agents to merchant systems. It is parallel to OpenAI's ACP, not the same thing, a distinction worth keeping straight (more on that below).
For a merchant: if your products are in a clean Google Merchant Center feed, you already have a foot in the largest, freshest AI shopping catalog. That feed is doing double duty now.
Perplexity: the answer engine that added a cart
Perplexity is the research-style answer engine, and it turned answers into a commerce channel with Buy with Pro, launched just before Black Friday 2025 in partnership with PayPal. Pro users in the US save their shipping and billing details once, then check out on select products from select merchants directly inside the answer, with free shipping on those orders.
For merchants, Perplexity runs a free Merchant Program to share product specs, gain eligibility for Buy with Pro, and get a dashboard of search and shopping trends. Notably, it has positioned itself as zero-fee to merchants, an explicit contrast with platforms that take a cut.
For a merchant: the Merchant Program is free and low-effort, which makes it one of the easier "get listed" moves on this whole map.
Amazon "Buy for Me": the agent that shops off-Amazon
Amazon's Buy for Me, piloted in April 2025 inside the Amazon app, is different in kind: it surfaces products from other retailers in Amazon search and has Amazon's AI complete the purchase on that retailer's own site for the shopper. It grew fast, from roughly 65,000 items at the beta to more than 500,000 by the end of 2025.
It is also the most contested surface. Amazon builds these listings from public product data, which drew pushback from brands that did not opt in and found themselves intermediated. That tension, brand versus gatekeeper, is the subject we return to later in the series.
For a merchant: you may already be in an AI aisle you never chose. Knowing it is the first step to deciding how you want to show up there.
The rails underneath: how an agent actually pays
A recommendation is not a sale until money moves. Through 2025 the card networks and Stripe built the payment layer that lets an agent authorize a purchase without ever touching a raw card number. The common trick is tokenization: a credential scoped to one agent, one merchant, and one spending policy, so a leaked token cannot be reused elsewhere.
- Mastercard Agent Pay (announced April 29, 2025) uses "Agentic Tokens" that bind a tokenized card to a specific agent, merchant scope, and consent policy, so an assistant can complete a checkout without holding the card number.
- Visa Intelligent Commerce (launched April 30, 2025, a day later) gives developers APIs to put payments, identity checks, and spending controls inside an agent. Visa has since added a single integration that also reaches non-Visa cards.
- Stripe powers ChatGPT's Instant Checkout and offers a Shared Payment Token scoped to a single merchant and basket, so the agent never sees the card details and you stay the merchant of record.
Who controls what (and where you still own the customer)
The most useful mental model is to separate the commerce protocol (how an agent finds products and places an order with you) from the payment layer (how the money is authorized). They stack; they are not rivals.
- ACP (Stripe + OpenAI) and UCP (Google) are two parallel commerce standards. Treat them as separate ecosystems you may need to support, not as one thing under two names.
- A payment-authorization layer sits beneath both. Google's AP2, for example, uses signed mandates so an agent can prove it was authorized to buy. We unpack that plumbing in a later post.
The encouraging part for merchants is the direction of control. These protocols are built to keep you as the merchant of record, owning the order, the payment relationship, and the customer data rather than renting them from a platform. OpenAI's 2026 pivot points the same way: when native in-chat checkout proved hard, the transaction drifted back toward the merchant's own checkout. The safe planning assumption is that AI will increasingly send you ready-to-buy customers, while the sale itself often closes on infrastructure you control.
That is also the line between healthy distribution and quiet disintermediation. Being listed everywhere is good. Being reduced to an interchangeable price-and-spec entry in someone else's aisle is not. Keeping the checkout, the data, and the brand on your side is how you stay a destination instead of a line item, a theme this series returns to head-on.
Do this now: find your aisles
You cannot manage surfaces you have not located. Pick the two or three your customers actually use and run the same category query in each, the way a shopper would (for example, "best wireless earbuds for running under $80"). For each surface, note three things:
- Do you appear? Absent on a surface means you are invisible to every agent that uses it.
- Is there a buy path? Check whether the answer offers a checkout, links to your site, or routes through a marketplace you do not control.
- Who controls the sale? If the purchase completes inside the platform, ask whether you are still the merchant of record and whether you get the customer's details.
Two fast wins fall out of this audit: make sure your products are in a clean Google Merchant Center feed (it now feeds the largest AI shopping catalog), and join Perplexity's free Merchant Program. Both are low-cost ways to claim shelf space while the aisles are still being built. Next in the series: why getting picked by AI on these surfaces is a different game than ranking on Google, and what actually moves the needle.
Frequently asked questions
Where do AI shopping agents actually appear today?
Mainly four discovery surfaces, each in the US first: ChatGPT (which added in-chat Instant Checkout with Etsy and Shopify merchants in September 2025), Google AI Mode and the Gemini app (which added agentic checkout in November 2025, backed by a Shopping Graph of more than 50 billion listings), Perplexity (whose Buy with Pro lets Pro users check out inside the answer), and the Amazon app (whose Buy for Me completes purchases on other retailers' sites). Underneath them sit the payment rails from Visa, Mastercard, and Stripe.
What is the difference between ACP and UCP?
They are two parallel commerce standards, not the same thing. The Agentic Commerce Protocol (ACP) was co-developed by Stripe and OpenAI and powers checkout in ChatGPT. The Universal Commerce Protocol (UCP) is Google's open standard for connecting agents to merchant systems in AI Mode and Gemini. Both describe how an agent finds products and completes a purchase with a merchant. A separate payment-authorization layer (such as Google's AP2) sits beneath them and handles the money. Do not conflate the two commerce protocols.
Does the AI platform or the merchant control the checkout and the customer?
It is shifting back toward the merchant. The protocols are designed to keep you as the merchant of record, so you own the order, the payment relationship, and the customer data. The direction of travel reinforces this: in March 2026 OpenAI scaled back native in-chat checkout and refocused ChatGPT on product discovery, pushing the actual transaction back to merchant-controlled paths. Treat in-chat checkout as in flux, and assume the final sale will often land on your own checkout.
How do AI agents pay without seeing my customer's card details?
Through tokenization. Visa Intelligent Commerce (launched April 30, 2025) and Mastercard Agent Pay (announced April 29, 2025) bind a tokenized card credential to a specific agent, a specific merchant, and a specific spending policy, so the agent can authorize one purchase without holding the raw card number. Stripe's Shared Payment Token does the same thing scoped to a single merchant and basket. The card network and PSP handle the secrets; the agent only carries a scoped permission to pay.
Sources & further reading: Stripe: Instant Checkout and the Agentic Commerce Protocol, OpenAI: powering product discovery in ChatGPT, Google: agentic checkout for holiday AI shopping, Perplexity: shop like a Pro (Buy with Pro), Amazon Buy for Me via DigitalCommerce360, Visa Intelligent Commerce, and Visa and Mastercard agent payments via DigitalCommerce360. Dates and figures are drawn from the cited announcements and reports; in-chat checkout mechanics are evolving, so treat them as a snapshot.