Agentic commerce, explained: what ACP and UCP mean for your store

What are the key facts about agentic commerce right now?

Checked on 7 October 2026. This area changes every few months, so the dates matter.

What is agentic commerce?

Agentic commerce is shopping where an AI assistant does part of the shopper's work: finding products, comparing them and, with permission, paying. Google describes it as AI that "completes tasks on people's behalf." Google

A real example: in November 2025 Google began rolling out agentic checkout in the U.S. A shopper tracks a price, and when it drops into budget, Google can "buy it for you on the merchant's site using Google Pay." Google says it will "always ask for your permission first." Google

An agent can buy from you in two ways:

1. Through your website, like a person. It clicks your buttons and fills in your checkout form. Our guide on making your website work for AI agents covers this route.
2. Through a direct connection to your store's systems. The agent asks for price and stock, builds a cart and passes payment details in a fixed format.

That fixed format is called a protocol: an agreed set of messages, like a standard order form both sides can read. ACP and UCP are the two big ones for shopping.

What is ACP, and can shoppers still buy inside ChatGPT?

ACP, the Agentic Commerce Protocol, is the open standard that connects ChatGPT to stores. As of 7 October 2026, OpenAI uses it mainly to help shoppers find products, and the purchase finishes on your own site.

Stripe and OpenAI built ACP together. It is open source under the Apache 2.0 license, and Stripe was the first payment provider to support it. ACP OpenAI's merchant page says ACP "supports product discovery and more accurate, personalized recommendations through shared product data," and that "over time, ACP will expand to support the full shopping journey." OpenAI

What happened to Instant Checkout?

The same page answers it: "We're moving away from a standalone Instant Checkout experience in ChatGPT." Shoppers "discover and evaluate products in ChatGPT, but purchases are completed on merchant-owned websites or apps." OpenAI Shopify agrees, calling ChatGPT "a discovery-focused referrer platform." Shopify Help Center

What ACP checkout was designed to need

The docs still describe three parts: a product feed, checkout endpoints that ChatGPT calls to start an order you accept or decline, and delegated payment, a one-time payment request with "a maximum chargeable amount and expiry." OpenAI

Today the feed is the part that counts, and feed onboarding is "currently available to approved partners." OpenAI

What is UCP, and how does checkout work in Google AI Mode and Gemini?

UCP, the Universal Commerce Protocol, is an open standard Google launched on 11 January 2026 that lets AI agents check out directly with a store, starting in AI Mode in Search and the Gemini app. Google

Google co-developed it with Shopify, Etsy, Wayfair, Target and Walmart, and more than 20 others endorsed it, including Mastercard, Stripe and Visa. Google Stores "remain the Merchant of Record." UCP

What the shopper sees

A Buy button on eligible product listings. Shoppers pay with Google Pay, using the cards and shipping details already saved in Google Wallet. Google says "you will remain the seller of record." Google Merchant Center Help

Stores can pick one of two paths. The native checkout path handles the whole purchase on Google. The cart path hands the shopper's cart over to your website to finish. Either way, Google must approve your integration "before you can go live." Google for Developers

How fast it is moving

• 19 March 2026: UCP added Cart, Catalog and Identity Linking, which gives signed-in shoppers their member prices. Google
• 20 May 2026: Google announced Universal Cart, a cart that works across stores. UCP checkout is to reach Canada and Australia "in the coming months, and later to the U.K." Google
• 16 September 2026: Google said UCP "already enables direct checkout for hundreds of thousands of brands and retailers." Google

UCP is spreading beyond Google. Microsoft says its Merchant Center "will support Universal Commerce Protocol." It also gives a useful split: "Feeds primarily enable discovery," while "UCP enables transactions." Microsoft Advertising Stripe lists both UCP and ACP for selling through agents. Stripe

What does my store have to provide before an AI agent can buy from it?

Three things: product data the agent can trust, a way to take the order, and a way to take the payment. Your platform or payment provider may handle the last two for you.

Sources: OpenAI, Google for Developers, Google Merchant Center Help.

How payment tokens keep the card safe

The agent never hands you the shopper's raw card. Stripe calls its shared payment token "a scoped grant to use the customer's payment method," with "usage and expiration limits." The agent sets the maximum amount to match the order total. Stripe

AP2, the Agent Payments Protocol, adds proof of what the shopper agreed to, using signed records called mandates for the cart and the payment. Google announced it on 16 September 2025, and FIDO Alliance working groups now carry the standard forward. AP2 Google UCP and AP2 are built to work together. Google Merchant Center Help

Who can join agentic checkout today, and how do I apply?

Most programs are open to small stores, but many are U.S.-only and some are still invite-based. Here is where each stood on 7 October 2026.

Sources: OpenAI, Google Merchant Center Help, Shopify Help Center, Microsoft Advertising, Stripe, PayPal.

OpenAI says a self-serve merchant platform is coming "later this year." OpenAI Google is rolling out a UCP integration hub inside Merchant Center in the U.S., "with Australia and Canada to follow next year." Google Merchant Center Help

Perplexity's in-chat checkout launched with PayPal. On 25 November 2025, PayPal said its merchants had become discoverable in Perplexity, with U.S. users able to check out in the chat. PayPal

ChatGPT also bars some products outright, such as alcohol, nicotine, weapons and prescription-only medicines. OpenAI

What should I do if my store runs on Shopify, WooCommerce or another platform?

Start in your platform's settings. Most small stores will join through their platform or payment provider, not by building ACP or UCP themselves. Google says so directly: if you use a platform, "connect directly with them" about their UCP plans. Google Merchant Center Help

Shopify

Agentic storefronts are "active by default for eligible stores." You manage them in Sales channels > Agentic, where the default setting, "Allow Shopify to manage for me," also signs you up for new AI channels automatically. Shopify Help Center

For direct checkout in Google AI Mode and Gemini, Shopify lists these rules Shopify Help Center:

• Your store is based in the U.S. and sells to U.S. customers.
• Your products are in Google Merchant Center, for example through the Google & YouTube channel with product and shipping sync turned on.
• Subscriptions, bundles, customizable products and B2B-only products aren't supported, and neither are local delivery or pickup.
• Google Analytics and custom pixels won't fire in that checkout.
• There are "no fees" beyond your normal payment processing.

Not on Shopify? Its Agentic plan, announced 11 January 2026, lets brands list products in Shopify Catalog "without needing to have a Shopify online store." Shopify

WooCommerce

WooCommerce's own status table lists UCP and ACP as "Coming soon" and MCP, a standard way for AI assistants to read your store, as live. Its advice is to install Google for WooCommerce, which syncs your catalog to Merchant Center, and Stripe for WooCommerce, which will add agentic checkout through Stripe. WooCommerce

Any other platform

Use the payment provider you already have: Stripe's suite Stripe or PayPal's Store Sync. PayPal Also set up Google Merchant Center and apply for ChatGPT feeds. Our guide on getting products into AI shopping walks through each feed.

What stays the same when AI agents do the buying?

Almost everything that makes a store good for people: accurate product data, current prices and stock, honest reviews and clear policies. The agent still has to choose you before it can buy.

Agents still rank products. OpenAI ranks merchants on "availability, price, quality, and whether they are the maker or primary seller." OpenAI Shopify's listing checks score description detail, image count, verified reviews, complete variants and store policies. Shopify Help Center

Wrong prices now break sales, not just trust. Stripe warns that price mismatches "cause checkouts to fail." It suggests sending stock and price updates about every 15 minutes, since an agent may keep calling an item sold out until it hears otherwise. Stripe

Policies are entry tickets. Google needs shipping and returns in Merchant Center. Shopify needs your terms, privacy and refund policies before Google checkout. Stripe asks for terms, privacy and returns when you sign up. Google for Developers Shopify Help Center Stripe

Our guide on showing prices to AI covers the price side.

Our advice: the protocols differ by company, but they all read the same inputs. Clean data serves ChatGPT, Gemini, Copilot, Perplexity and the next agent too.

What should be on a small store's agentic commerce checklist?

To see whether AI assistants already recommend your products, ask them what your shoppers ask. Our Prompt Simulator runs one question across many AI engines at once and shows the sources each one used.

Sources

1. Power product discovery in ChatGPT — OpenAI. Read Oct 7, 2026.
2. Key concepts – Agentic Commerce — OpenAI. Read Oct 7, 2026.
3. Get Started – Agentic Commerce — OpenAI. Read Oct 7, 2026.
4. Shopping with ChatGPT Search — OpenAI. Read Oct 7, 2026.
5. Agentic Commerce Protocol — Agentic Commerce Protocol (OpenAI and Stripe). Read Oct 7, 2026.
6. Agentic commerce — Stripe. Read Oct 7, 2026.
7. Sell through agents — Stripe. Read Oct 7, 2026.
8. Shared payment tokens — Stripe. Read Oct 7, 2026.
9. New tech and tools for retailers to succeed in an agentic shopping era — Google. Read Oct 7, 2026.
10. AI shopping gets simpler with Universal Commerce Protocol updates — Google. Read Oct 7, 2026.
11. How we're helping retailers thrive with new Universal Commerce Protocol features and AI tools on Google — Google. Read Oct 7, 2026.
12. Boost your holiday sales with these agentic commerce updates — Google. Read Oct 7, 2026.
13. Let AI do the hard parts of your holiday shopping — Google. Read Oct 7, 2026.
14. About the Universal Commerce Protocol (UCP) and UCP-powered checkout feature on Google — Google Merchant Center Help. Read Oct 7, 2026.
15. How to onboard to the UCP integration hub in Merchant Center — Google Merchant Center Help. Read Oct 7, 2026.
16. Google Universal Commerce Protocol (UCP) Guide: Overview — Google for Developers. Read Oct 7, 2026.
17. Universal Commerce Protocol — Universal Commerce Protocol. Read Oct 7, 2026.
18. Agent Payments Protocol (AP2) — AP2. Read Oct 7, 2026.
19. The agentic commerce platform: Shopify connects any merchant to every AI conversation — Shopify. Read Oct 7, 2026.
20. Shopify agentic storefronts — Shopify Help Center. Read Oct 7, 2026.
21. Managing agentic storefronts — Shopify Help Center. Read Oct 7, 2026.
22. Selling on Google AI Mode and Gemini — Shopify Help Center. Read Oct 7, 2026.
23. Make your store visible to AI agents — WooCommerce. Read Oct 7, 2026.
24. PayPal Agentic Commerce Services — PayPal. Read Oct 7, 2026.
25. PayPal and Perplexity Launch Instant Buy Ahead of Black Friday — PayPal. Read Oct 7, 2026.
26. Agentic Commerce — Microsoft Advertising. Read Oct 7, 2026.