<\/p>
Google\u2019s Universal Commerce Protocol can now handle shopping carts, live catalog queries, and loyalty program benefits for AI agent transactions. On March 19, Google\u00a0announced three new UCP capabilities\u00a0and a simplified onboarding path through Merchant Center, two months after Google and Shopify\u00a0unveiled UCP\u00a0at the National Retail Federation conference in January 2026.<\/p>
The January launch had a big coalition (Mastercard, Visa, Walmart, Target, Best Buy) but limited functionality. UCP could handle single-item checkout sessions and not much else. The March update closes the gap between UCP\u2019s ambition and UCP\u2019s practical capability.<\/p>
I covered UCP in depth in\u00a0Selling to AI: The Complete Guide to Agentic Commerce, where I compared UCP to OpenAI and Stripe\u2019s Agentic Commerce Protocol (ACP). This article covers what changed in March and what the changes mean for retailers.<\/p>
Cart.<\/strong>\u00a0UCP\u2019s new Cart capability lets AI agents add multiple items to a shopping cart from a single retailer in one operation. Until March 2026, UCP only supported single-item checkout sessions, meaning an agent buying three products from one store needed three separate transactions. The Cart capability also supports pre-purchase exploration: agents can build baskets before a shopper commits, then convert the basket to a checkout session when the shopper is ready. UCP Cart is currently published as a draft specification.<\/p> Catalog.<\/strong>\u00a0UCP\u2019s new Catalog capability lets agents query real-time product details directly from a retailer\u2019s inventory, including variants, pricing, and stock levels. The difference between Catalog and existing Google Shopping product feeds: product feeds are static snapshots updated periodically, while Catalog provides live data at the moment of the query. An agent using Catalog can check whether a specific size is in stock before presenting the product to a shopper. UCP Catalog is also a draft specification.<\/p> Identity Linking.<\/strong>\u00a0UCP\u2019s Identity Linking capability lets shoppers connect retailer accounts to UCP-integrated platforms using OAuth 2.0. When a shopper with a Nike membership buys through Google AI Mode, Identity Linking carries over that shopper\u2019s member pricing, discounts, and free shipping. Without Identity Linking, shopping through an AI agent means losing the loyalty benefits a shopper would get when logged into the retailer\u2019s website directly. Identity Linking is the only capability in this update already in UCP\u2019s stable release rather than draft.<\/p> Google is building a simplified UCP onboarding process directly in Merchant Center, targeting retailers who don\u2019t have engineering teams to implement a protocol from scratch. Google says the Merchant Center UCP rollout will happen \u201cover the coming months.\u201d<\/p> One concrete detail: products using the\u00a0native_commerce<\/span>\u00a0product attribute will display a checkout button in Google AI Mode and the Gemini app. For retailers already managing product feeds through Google Merchant Center, UCP onboarding should be a settings change rather than an integration project.<\/p> Commerce Inc, Salesforce, and Stripe will implement UCP on their platforms, with Google describing the timeline as \u201cin the near future.\u201d Retailers on Commerce Inc, Salesforce, or Stripe won\u2019t need to implement UCP directly. The platform handles the protocol layer, similar to how Shopify\u2019s Agentic Storefronts already abstract away multi-protocol complexity for Shopify merchants.<\/p> Salesforce\u2019s dual-protocol position is notable. Salesforce\u00a0announced ACP support\u00a0in October 2025. With UCP support coming too, Salesforce Commerce Cloud merchants will be able to serve both protocols from a single platform, reaching AI agents on ChatGPT (via ACP) and Google AI Mode (via UCP) without separate integrations.<\/p> Stripe occupies an even more central position. Stripe\u00a0co-created ACP\u00a0with OpenAI and is now implementing UCP as well. Stripe is becoming the shared payment layer across both competing agentic commerce protocols.<\/p> UCP\u2019s January announcement was a statement of intent. UCP\u2019s March update is a statement of readiness. Three things stand out:<\/p> UCP is reaching feature parity with ACP.<\/strong>\u00a0OpenAI and Stripe\u2019s Agentic Commerce Protocol launched in September 2025 with cart management and catalog access built in from day one. UCP launched in January 2026 without either capability. Cart, Catalog, and Identity Linking close that gap, giving UCP the core primitives AI shopping agents need to handle multi-item, loyalty-aware transactions.<\/p> Google\u2019s onboarding play targets mass adoption, not enterprise showcases.<\/strong>\u00a0Google wants millions of Merchant Center retailers on UCP, not just the enterprise brands (Walmart, Target, Best Buy) that endorsed UCP at NRF. Merchant Center integration is how Google reaches that scale. A retailer managing Google Shopping feeds today could become UCP-enabled without writing a line of code.<\/p> Identity Linking is UCP\u2019s clearest differentiator over ACP.<\/strong>\u00a0Neither ACP nor any other agentic commerce protocol offers an equivalent to Identity Linking. Identity Linking solves a specific adoption barrier: shoppers lose loyalty pricing, member discounts, and free shipping when buying through an AI agent instead of logging into a retailer\u2019s website directly. Removing that friction makes agentic commerce more attractive to both retailers protecting their loyalty programs and shoppers unwilling to give up membership benefits.<\/p> For businesses already thinking about\u00a0agentic commerce, the action items remain the same: clean product data, structured markup, and being on a platform that handles protocol complexity. What changed in March is that UCP is no longer a specification to watch. Google is building UCP into the infrastructure retailers already use.<\/p> More Resources:<\/strong><\/p> This post was originally published on No Hacks.<\/em><\/p> Featured Image: Inkoly\/Shutterstock<\/em><\/p> <\/div> Ecommerce,Generative AI#Googles #UCP #Update #Carts #Catalogs #Loyalty #Shopping #sejournal #slobodanmanic1778414608<\/p> ","protected":false},"excerpt":{"rendered":" Google\u2019s Universal Commerce Protocol can now handle shopping carts, live catalog queries, and loyalty program benefits for AI agent transactions. On March 19, Google\u00a0announced three new UCP capabilities\u00a0and a simplified onboarding path through Merchant Center, two months after Google and Shopify\u00a0unveiled UCP\u00a0at the National Retail Federation conference in January 2026. The January launch had a […]<\/p>\n","protected":false},"author":1,"featured_media":7872,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[29279,29280,179,29281,80,1638,18507,1898,92],"class_list":["post-7871","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-accessibility","tag-carts","tag-catalogs","tag-googles","tag-loyalty","tag-sejournal","tag-shopping","tag-slobodanmanic","tag-ucp","tag-update"],"acf":[],"_links":{"self":[{"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=\/wp\/v2\/posts\/7871","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7871"}],"version-history":[{"count":0,"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=\/wp\/v2\/posts\/7871\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=\/wp\/v2\/media\/7872"}],"wp:attachment":[{"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7871"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7871"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/longzhuplatform.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7871"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Simplified Onboarding<\/h2>
Platform Partners<\/h2>
What This Means<\/h2>