Google has expanded the Universal Commerce Protocol with cart, catalogue, and identity linking capabilities to optimise agentic commerce.
The updates extend the UCP framework with three optional features: a cart function enabling AI agents to save or add multiple items from a single retailer simultaneously, a catalogue capability allowing agents to retrieve real-time product data (including variants, inventory, and pricing) directly from a retailer's product feed, and an identity linking feature that connects a shopper's account across UCP-integrated platforms to their existing loyalty or membership profile on a given retailer's site, preserving associated benefits such as member pricing or complimentary shipping.
Simplifying retailer onboarding
According to the official press release, alongside the capability updates, Google is rolling out a streamlined UCP onboarding process through Google's Merchant Center over the coming months. The move is intended to lower the barrier to entry for retailers of varying sizes seeking to participate in agentic commerce experiences across Google Search's AI Mode and the Gemini app.
Commerce platform providers Commerce Inc, Salesforce, and Stripe are expected to implement UCP across their respective platforms in the near term, with additional partners to follow. Through the process of embedding UCP at the platform level, the protocol can reach a broader base of merchants without requiring individual technical integration by each retailer.
Agentic commerce infrastructure
The UCP was designed as an open standard to allow AI agents to interact with ecommerce environments on behalf of users. The identity linking addition is particularly relevant in the context of fragmented digital shopping, where consumers frequently lose access to loyalty benefits when transacting outside a retailer's own channels. In addition, by standardising the mechanism through which agents authenticate user identity across platforms, UCP aims to make agent-driven purchases functionally equivalent to direct site transactions.
As an open standard, UCP adopters retain the flexibility to select which capabilities they support, allowing for phased or selective implementation depending on technical readiness or business requirements.
The rollout of a simplified onboarding path via Merchant Center, combined with platform-level adoption by major commerce infrastructure providers, signals a move towards broader ecosystem standardisation of agentic shopping interactions, a segment that has seen growing interest from both technology providers and retailers as AI-assisted purchasing becomes more prevalent.
