What is agentic commerce?
There is no formal definition from a standards body yet. OpenAI used the term when it launched Instant Checkout on 29 September 2025: "ChatGPT doesn't just help you find what to buy, it also helps you buy it" (OpenAI, read 1 November 2026).
On 24 March 2026, OpenAI changed course. It wrote that "the initial version of Instant Checkout did not offer the level of flexibility that we aspire to provide". Merchants can now use their own checkout, and OpenAI focuses on product discovery (OpenAI, read 1 November 2026).
Stripe, which built the protocol behind it with OpenAI, describes the same idea without a one-line definition: AI agents act for buyers in their purchases from businesses (Stripe).
Which protocols exist for agentic commerce?
| Agentic Commerce Protocol (ACP) | Agent Payments Protocol (AP2) | |
|---|---|---|
| Built by | Stripe and OpenAI | Google, with "more than 60 organizations" |
| Announced | 29 September 2025 | 16 September 2025 |
| What it does | Lets an agent such as ChatGPT pass an order to the merchant's checkout | Uses signed "mandates" as proof of what the user approved |
| Licence or relation | "open source, Apache 2.0 licensed" | Can extend the A2A protocol and MCP |
| Source | Stripe, OpenAI | Google Cloud |
Read on each company's own pages on 1 November 2026. Launch details may have changed since the announcements.
How does agentic checkout work?
OpenAI's docs describe the ACP checkout flow as it works inside ChatGPT (OpenAI commerce docs):
- The merchant shares a product feed (CSV or JSON) with prices and stock.
- A user asks a shopping question in ChatGPT.
- ChatGPT shows products. At launch, OpenAI said product results are "organic and unsponsored" (OpenAI).
- The user taps Buy and confirms the order, shipping and payment.
- ChatGPT sends the order to the merchant through the protocol.
- The merchant accepts it, takes payment with its own provider and ships it.
OpenAI states: "OpenAI is not the merchant of record in the Agentic Commerce Protocol." The merchant keeps the customer relationship.
Since March 2026, this in-chat checkout is no longer the only route. A merchant can send the buyer to its own checkout instead (OpenAI).
Why does agentic commerce matter for B2B SaaS?
At launch it was about consumer goods: US Etsy sellers first, with Shopify merchants announced as "coming soon". The March 2026 update is about shopping too. For B2B software, the nearer effect is the research step. An AI agent building a shortlist reads list articles and pricing pages, then compares what it finds.
In its launch post, OpenAI said that when several merchants sell the same product, ChatGPT considers "availability, price, quality" and other factors. The lesson for software brands is simple: keep product facts current and written in plain text, on your own site and in the lists that mention you.
What does it look like? (hypothetical example)
This example is hypothetical. A buyer asks: "Order me a webcam under $80 that works with Zoom." The agent shows three options. The buyer picks one and confirms. The agent sends the order to the shop, and the shop charges the card and ships it. The buyer never visits the shop's site.
Agentic commerce vs agentic search vs ads
- Agentic search finds and compares. Agentic commerce also completes the purchase.
- ChatGPT ads are paid and labeled. At launch, OpenAI said Instant Checkout items "are not preferred in product results".
- An AI agent is the software that does the work in both.
For how brands get named in AI answers in the first place, see LLM SEO: how B2B SaaS brands get named in AI answers.