--- title: "Universal Commerce Protocol (UCP): What It Is and What It Means for B2B on Shopify" url: https://www.uncap.com/post/universal-commerce-protocol-ucp author: "Denis Dyli" published: 2026-10-18 updated: 2026-10-18 summary: "The Universal Commerce Protocol (UCP) is an open-source standard, under the Apache License 2.0, that lets AI agents and businesses discover each other's capabilities and transact. Shopify and Google co-developed it and announced it on January 11, 2026; its four dated releases run to 2026-08-25, which adds payment terms such as deposits and deferred payment schedules. Shopify merchants are UCP-enabled by default, and Google's UCP-powered checkout in AI Mode and Gemini is available to select merchants. The spec is written for B2B, naming procurement systems, suppliers and distributors, but Shopify's agentic storefronts support only direct-to-consumer sales and don't display B2B pricing." --- # Universal Commerce Protocol (UCP): What It Is and What It Means for B2B on Shopify > The Universal Commerce Protocol (UCP) is an open-source standard, under the Apache License 2.0, that lets AI agents and businesses discover each other's capabilities and transact. Shopify and Google co-developed it and announced it on January 11, 2026; its four dated releases run to 2026-08-25, which adds payment terms such as deposits and deferred payment schedules. Shopify merchants are UCP-enabled by default, and Google's UCP-powered checkout in AI Mode and Gemini is available to select merchants. The spec is written for B2B, naming procurement systems, suppliers and distributors, but Shopify's agentic storefronts support only direct-to-consumer sales and don't display B2B pricing. The Universal Commerce Protocol (UCP) is an open standard that gives AI agents and businesses one shared way to handle commerce, from finding products to checkout and orders. Shopify and Google co-developed it and announced it on January 11, 2026. It is open source, and Shopify says its merchants are UCP-enabled by default. For B2B, there is a catch: the spec covers B2B, but Shopify's AI channels sell to consumers only today. Where this guide gives Uncap's own view, it says so. **Key takeaways** - What it is: an open-source standard (Apache License 2.0) for agents and businesses to transact. - Who built it: Shopify and Google, with Etsy, Wayfair, Target and Walmart named by Google as co-developers. - Versions: four dated releases. The latest, 2026-08-25, adds deferred payments, deposits and installment schedules. - For B2B: the spec names procurement systems, suppliers and distributors, but Shopify's agentic storefronts "support only direct-to-consumer (D2C) sales." ## What is the Universal Commerce Protocol? The [UCP spec](https://ucp.dev/documentation/core-concepts/) defines itself like this: "The Universal Commerce Protocol (UCP) is an open standard for interoperability between commerce entities. It defines a common language and functional primitives so that platforms and businesses can interoperate securely and reliably across commercial verticals." In plain terms, it is a shared rulebook. An agent that speaks UCP can ask any business that speaks it what it supports, then shop and check out in the same common language with each one. The problem it solves is integration sprawl. [Google's developer blog](https://developers.googleblog.com/under-the-hood-universal-commerce-protocol-ucp/) describes businesses facing "an N x N integration bottleneck, forcing them to build bespoke connections for every surface." UCP replaces that grid with one machine-readable profile per business that any compatible agent can read. Is UCP public or private? Public. The [GitHub repository](https://github.com/universal-commerce-protocol/ucp) says "UCP is an open-source project under the Apache License 2.0 and is open to contributions from the community." For a merchant, UCP is plumbing. You won't log in to it, but it shapes what an agent can do with your store. If the bigger idea is new to you, start with [what agentic commerce is](https://www.uncap.com/post/agentic-commerce-b2b-guide-shopify). ## Who built UCP, and when it launched UCP was announced on January 11, 2026. [Shopify's newsroom](https://www.shopify.com/news/ai-commerce-at-scale) called it "a new open standard co-developed with Google to bring commerce to agents at scale." [Google's announcement](https://blog.google/products/ads-commerce/agentic-commerce-ai-tools-protocol-retailers-platforms/) the same day said "UCP was co-developed with industry leaders including Shopify, Etsy, Wayfair, Target and Walmart, and endorsed by more than 20 others across the ecosystem like Adyen, American Express, Best Buy, Flipkart, Macy's Inc., Mastercard, Stripe, The Home Depot, Visa and Zalando." So it isn't Google's protocol or Shopify's alone. Ilya Grigorik, a Distinguished Engineer at Shopify, wrote in [Building the Universal Commerce Protocol](https://shopify.engineering/UCP): "We co-developed UCP with Google to create an open standard for AI agents to connect and transact with any merchant." The group has grown. In October 2026, the [ucp.dev](https://ucp.dev/) home page lists shopping co-developers Google, Shopify, Etsy, Wayfair, Target, Walmart, Amazon, Microsoft, Meta, Salesforce and Stripe, plus separate groups for lodging and food. Its banner reads: "UCP is expanding beyond retail: Lodging draft specification now available. Food coming soon." ## How UCP works: roles, profiles and negotiation UCP starts with roles. The spec says "UCP defines the interactions between four distinct actors": - Platform: the side that consumes capabilities. The spec's examples: "AI Shopping Assistants, Super Apps, Search Engines, B2B Procurement Systems." - Business: the side that exposes capabilities, typically the merchant of record. Examples: "Retailers, Airlines, Hotel Chains, Service Providers, Suppliers, Distributors." - Credential Provider: manages sensitive data such as payment instruments and shipping addresses, for example a digital wallet. - Payment Service Provider: authorizes and captures the payment. Then discovery: "Every business publishes a machine-readable profile at /.well-known/ucp that declares which services, capabilities, and payment handlers they support." The agent points to its own profile on each request. Negotiation follows. "Capability negotiation follows a server-selects architecture." The business keeps only capabilities both profiles declare, at the latest version both support. "The result is a minimal, mutually compatible capability set." Shopify's engineering post sums it up: "Agents discover these capabilities, negotiate what they can handle, and proceed to complete transactions." The same post describes checkout as "a simple checkout state machine" with three states: `incomplete`, `requires_escalation` and `ready_for_complete`. When the agent can't finish, "The buyer follows continue_url and picks up exactly where the agent left off." And [Shopify's UCP page](https://www.shopify.com/ucp) says: "Payment handlers are negotiated, not prescribed." ## What UCP covers today: capabilities and versions The spec calls capabilities "discrete, versioned features that a Business declares it supports," the verbs of the protocol. Its current examples include: - dev.ucp.shopping.catalog.search and dev.ucp.shopping.catalog.lookup : "Search across a business catalog" and "Retrieve a specific product by ID". - dev.ucp.shopping.cart : "Pre-checkout cart management". - dev.ucp.shopping.checkout : "Initiates and completes purchase sessions". - dev.ucp.shopping.order : "Order lifecycle events". - dev.ucp.common.identity_linking : "OAuth-based account linking". Extensions add detail on top, such as discount codes, shipping options, loyalty and payment terms. Versions are dates: "UCP uses date-based version identifiers (YYYY-MM-DD)." The [GitHub releases](https://github.com/universal-commerce-protocol/ucp/releases) show four: 2026-01-11, 2026-01-23, 2026-04-08 and 2026-08-25, which ucp.dev marks as the latest. The 2026-04-08 notes add Cart and Catalog Search and Lookup, which Google announced as "new optional capabilities" on [March 19, 2026](https://blog.google/products-and-platforms/products/shopping/ucp-updates/), along with Identity Linking. The 2026-08-25 release "introduces major protocol enhancements, key structural refactorings to support multi-vertical expansion, payments security improvements (3DS2) and structured request constraints, independent capability versioning, and grocery vertical readiness." For B2B readers, one line stands out: "Payment Terms & Schedules: Deferred payments, deposits, and installment schedules, along with multi-instrument Split Payments." ## UCP vs ACP, AP2 and MCP Four acronyms show up next to UCP: - ACP (Agentic Commerce Protocol): Stripe's announcement of September 29, 2025 calls it "a new open standard codeveloped by Stripe and OpenAI that enables programmatic commerce flows between buyers, AI agents, and businesses." The ACP site adds: "ACP is open source and community-designed under the Apache 2.0 license." - AP2 (Agent Payments Protocol): Google's protocol for agent-led payments, which Google says it introduced the year before UCP. - MCP (Model Context Protocol): "an open-source standard for connecting AI applications to external systems," per its documentation . A general connector, not a commerce standard. - A2A (Agent2Agent): listed in the UCP spec for "Agent-to-Agent protocol integrations." Google says UCP is compatible with A2A, AP2 and MCP. The spec lists REST, MCP, A2A and embedded as ways to reach the same service: "an AI agent may prefer MCP, a traditional web app may use REST." So MCP can carry UCP, and UCP defines the commerce. UCP and ACP, by contrast, are separate open standards for agent commerce from different authors. For a Shopify merchant, the practical choice is the channel, not the protocol. You pick which AI channels get your products in your Shopify admin, as the next section explains. ## UCP on Shopify: what you already have Shopify's [Spring '26 Edition](https://www.shopify.com/news/spring-26-edition-merchant), dated June 17, 2026, says: "Shopify merchants are UCP-enabled by default, so any surface that builds with it incorporates a merchant's specific checkout rules, discounts, and customizations." There is nothing to install. On September 4, 2026, the [Shopify developer changelog](https://shopify.dev/changelog/posts/08-25-is-now-supported) said "Shopify storefronts now advertise support for Universal Commerce Protocol (UCP) version 2026-08-25 in their discovery profiles at /.well-known/ucp." It also says: "The set of capabilities that Shopify supports is unchanged." A new spec version doesn't make every new spec feature live on your store. What you manage is the channels. Shopify says "You manage your agentic storefronts setup from Sales channels > Agentic in your Shopify admin," and the default, Allow Shopify to manage for me, "means that all channels are active." Our guide to [Shopify Agentic Storefronts for B2B](https://www.uncap.com/post/shopify-agentic-storefronts-b2b) walks through each channel and setting. For developers, [Shopify's agent docs](https://shopify.dev/docs/agents) cover "Shopify's UCP-compliant MCP servers" and a Universal Cart API that is behind an early access waitlist. ## UCP on Google: checkout in AI Mode and Gemini Google uses UCP for checkout in its AI surfaces. Its [Merchant Center help page](https://support.google.com/merchants/answer/16837055) says: "By integrating with UCP, you can implement a checkout button on eligible product listings in AI Mode in Google Search and on Gemini." Is it live? "The checkout feature enabled by UCP is available for select merchants at this time," and the page "only applies to products with eligibility in the United States, Canada, and Australia, and for participating merchants and partners." Google's [developer guide](https://developers.google.com/merchant/ucp) adds: "You remain the Merchant of Record." For Shopify merchants, the route is Shopify's [Google AI Mode and Gemini channel](https://help.shopify.com/en/manual/online-sales-channels/agentic-storefronts/google): "Your store must be based in the United States and you must sell to customers in the United States," with "a valid Google Merchant Center account." It "is rolling out to eligible stores," and direct checkout "might not yet be available in your store." In that direct checkout, [Shopify Functions](https://www.uncap.com/glossary/shopify-functions) for shipping, discounts and validation run too, and B2B-only products aren't supported. ## What UCP means for B2B sellers The spec is written for B2B. Its roles "are defined by direction of capability flow, not by industry vertical, making UCP equally applicable to B2C, B2B, and agent-to-agent commerce." Its examples include "B2B Procurement Systems" and "Suppliers, Distributors," and the 2026-08-25 release added a payment terms extension for "Deposits, installments, and deferred payment schedules." As noted above, Shopify's own capability set did not change with that version. Shopify's AI channels draw a different line today. [Shopify's Help Center](https://help.shopify.com/en/manual/online-sales-channels/agentic-storefronts/products) says: "Shopify's agentic storefronts support only direct-to-consumer (D2C) sales. Products that are sold exclusively to business or wholesale customers are automatically excluded from AI channels when Shopify can identify them." For shared products, "B2B pricing doesn't display on agentic storefronts." A distributor that sells one pump to contractors at contract prices and to homeowners at retail shows only the D2C price in AI channels. Shopify also warns that if you gate wholesale with "third-party apps or custom theme modifications," it "might not be able to detect" those products as B2B-only. Uncap's view: the protocol is ahead of the channels, so prepare now and promise nothing yet. Run wholesale on native Shopify B2B catalogs and companies; see [whether Shopify is good for B2B](https://www.uncap.com/post/is-shopify-good-for-b2b) and our playbook on [running B2B and DTC from one Shopify store](https://www.uncap.com/post/running-b2b-dtc-one-shopify-store). Keep [contract pricing](https://www.uncap.com/post/how-to-run-contract-pricing-cleanly-on-shopify-b2b) and [net terms](https://www.uncap.com/post/shopify-net-terms) in your B2B setup. Then fix the data agents do read: Shopify Catalog sends "your latest inventory and prices," and [Uncap Connect](https://www.uncap.com/products/connect) moves inventory and pricing between your ERP and Shopify the moment they change, with the ERP as [system of record](https://www.uncap.com/glossary/system-of-record). If your buyers order from procurement systems, see our guide to [punchout catalogs on Shopify B2B](https://www.uncap.com/post/punchout-catalogs-shopify-b2b). For the buyer side, see [how B2B buyers use AI agents to shortlist suppliers](https://www.uncap.com/post/ai-agents-b2b-buying). ## What to do now In the order we'd tackle it: - Check what agents can read. The search preview in Sales channels > Agentic shows listing insights, from "Description completeness" to "Variant & option completeness". The variant check flags names with "acronyms or numbers that are hard for agents to understand or recommend," which hits part-number catalogs hardest. - Complete your policies. Shopify's Google channel requires your "Terms of service, Privacy policy, and Return and refund policy completed in Settings > Policies." - Connect Google Merchant Center if Google's surfaces matter, since Shopify says discovery there "is powered by Google Merchant Center." - Decide your B2B exposure, starting with anything gated by an app or theme code. - Fix product data at the source, in your ERP or PIM , before it syncs. - Plan before you build. Uncap Blueprint is a fixed $7,500, delivered in four weeks, and maps architecture and integrations before you commit. When you want a team on it, see how we approach [getting your Shopify store agent-ready](https://www.uncap.com/solutions/agentic-commerce). [Talk to Our Experts](https://www.uncap.com/quote), and bring your catalog and ERP questions with you. ## Frequently asked questions ### What is the Universal Commerce Protocol (UCP)? UCP is an open standard that lets AI agents and businesses discover each other's capabilities and complete purchases, from catalog search to checkout and orders. Shopify and Google co-developed it. ### Who created UCP? Shopify and Google co-developed UCP. Google's launch post also names Etsy, Wayfair, Target and Walmart as co-developers. As of October 2026, ucp.dev also lists Amazon, Microsoft, Meta, Salesforce and Stripe among its shopping co-developers. ### When did UCP launch? UCP launched on January 11, 2026, and its first version is dated 2026-01-11. Later versions are dated 2026-01-23, 2026-04-08 and 2026-08-25, the latest. ### Is UCP open source? Yes. UCP is an open-source project under the Apache License 2.0, published on ucp.dev and GitHub and open to community contributions. ### Is UCP the same as the Agentic Commerce Protocol (ACP)? No. ACP is a separate open standard, codeveloped by Stripe and OpenAI and announced on September 29, 2025. UCP was co-developed by Shopify and Google. Both use the Apache 2.0 license. ### What is the difference between MCP and UCP? MCP is a general standard for connecting AI applications to external systems, while UCP is a commerce standard. The UCP spec lists MCP as one transport for reaching a business's commerce services, alongside REST, A2A and embedded. ### Do Shopify merchants need to do anything to use UCP? Not for the protocol itself: Shopify says its merchants are "UCP-enabled by default." You choose which AI channels get your products, in Sales channels > Agentic. ### Is UCP live on Google? Partly. Google says its UCP-powered checkout in AI Mode and Gemini "is available for select merchants at this time." Shopify's Google channel requires a US-based store and is still rolling out. ### Does UCP support B2B? The spec does, but Shopify's AI channels don't today. UCP calls itself "equally applicable to B2C, B2B, and agent-to-agent commerce." Shopify's agentic storefronts sell D2C only, exclude B2B-only products they can identify, and show the D2C price for shared products.