Agentic commerce arrives: what UCP changes for e-commerce

In part one, we explored how AI changed content discovery, but discovery is only half the equation when someone finds your product through AI. Do they leave the conversation to visit your website, or does the entire transaction happen without them ever clicking away? Google's Universal Commerce Protocol makes the second scenario possible, and it fundamentally changes how e-commerce works. 

For e-commerce businesses, this represents the most significant shift since mobile commerce. How quickly you adapt to agentic commerce will determine whether you lead or follow. 

What is UCP? 

The Universal Commerce Protocol is an open standard that establishes a common language for AI agents and systems to work together across the complete shopping journey, from discovery to purchase to post-sale support. 

Co-developed with Shopify, Etsy, Wayfair, Target and Walmart, and endorsed by over 20 major retailers and payment providers, UCP represents a coordinated industry response to a fundamental question. How do we enable commerce when AI agents become the interface? 

Unlike previous optimisation strategies focused on visibility, UCP addresses the entire transactional journey. Users can discover products, compare options, make purchasing decisions and complete checkout, all without leaving their conversation with Gemini, Google AI Mode or other compatible AI platforms. 

Understanding the Competitive Landscape 

UCP doesn't exist in isolation. Three distinct approaches to agentic commerce are emerging. 

OpenAI and Stripe's ACP launched in September 2025 to power ChatGPT's Instant Checkout feature. The Agentic Commerce Protocol is: 

• Highly optimised around Stripe's payment infrastructure and OpenAI's ecosystem 

• Tightly scoped, opinionated and designed for rapid deployment within ChatGPT 

Stripe's Agentic Commerce Suite arrived in December 2025. Recognising that the agentic commerce landscape would quickly fragment across multiple AI platforms, Stripe pivoted from ACP-specific support to multi-agent compatibility. The Suite: 

• Provides a single integration that enables merchants to sell across multiple AI agents without maintaining separate integrations for each platform 

• Provides multi-agent reach through Stripe's infrastructure whilst maintaining their payment processing as the core offering 

This shift acknowledges what Google's UCP was designed to address. Merchants need to reach customers wherever AI conversations happen, not just on a single platform. 

Google's UCP approach takes a different route. It's more decentralised and ecosystem-oriented, built to work across multiple platforms and payment providers from inception. Where ACP requires merchants to go through a centralised listing process, UCP: 

• Allows merchants to publish their commerce capabilities directly on their own domains 

• Makes these capabilities discoverable by any compatible AI agent 

Stripe's Suite sits somewhere between, providing multi-agent reach through Stripe's infrastructure whilst maintaining their payment processing as the core offering. 

UCP builds on existing protocols including: 

• Agent2Agent (A2A) 

• Agent Payments Protocol (AP2) 

• Agent-to-User Interface (A2UI) 

• Model Context Protocol (MCP) 

What makes UCP significant is that whilst its fulfilment and identity functionality is currently limited compared to some proprietary solutions, it's designed to integrate into an existing ecosystem of these protocols. This means it can kickstart a marketplace in ways that more closed protocols cannot. Merchants using existing commerce infrastructure can participate without wholesale platform migration. 

Business Agent and Brand Control 

Alongside UCP, Google introduced Business Agent, a feature that allows retailers to create branded conversational experiences directly within Google Search and Gemini. Merchants can customise the agent's appearance with brand colours and messaging, train it on business-specific data like brand guidelines and size guides, and answer product questions in the brand's voice. 

What This Means for E-Commerce Businesses 

Product data becomes critical. AI agents rely on rich, structured product information beyond traditional keywords. Your product catalogue needs to answer questions AI systems will ask on behalf of users, not just match search terms. 

Checkout friction disappears. Transactions happen within the AI conversation, making abandoned cart recovery irrelevant. The traditional funnel collapses into a conversation where intent and fulfilment happen in rapid succession. 

Platform integration becomes critical. UCP is compatible with existing protocols, including Model Context Protocol (MCP). Organisations will need to understand how their content and commerce systems connect to these emerging protocols. 

The Strategic Imperative 

The organisations that will dominate agentic commerce aren't waiting for perfect clarity. They're taking specific actions now. 

1. Audit your product data. Review your current product information architecture. Can AI systems extract clear, accurate answers about specifications, compatibility, use cases and availability? 

2. Structure for AI consumption. Implement schema markup, enrich product attributes and create structured content that AI can reliably interpret and present. 

3. Choose your protocol strategy. Evaluate whether UCP, ACP, Stripe's Suite or a combination makes sense for your business based on where your customers have AI-powered conversations. 

4. Test and measure. Begin tracking how your products appear in AI-generated shopping responses. Understand which product attributes AI systems prioritise and which information gaps cause your products to be excluded. 

5. Prepare your teams. Your commerce teams need to understand agentic workflows, not just traditional e-commerce operations. This requires training, new processes and potentially new roles. 

Moving to Agentic Commerce 

Your digital experience platform either enables agentic commerce or becomes a constraint. The technical capabilities matter, but organisational readiness determines whether you can actually execute. 

Conversion now happens inside interfaces you don't control. The organisations moving first will define how this market develops. 

The gap between understanding UCP and implementing it is where most organisations stall. We make sure you don't.