Glossary of Terms
Key terminology for understanding agentic commerce and the Universal Commerce Protocol ecosystem.
Agentic Commerce
The emerging paradigm where AI agents act on behalf of users to discover, compare, and facilitate purchases. Rather than users browsing websites directly, AI assistants like ChatGPT, Claude, or Google's Gemini search for products, evaluate options, and guide purchase decisions. This represents a fundamental shift in how commerce happens online.
Universal Commerce Protocol (UCP)
Shopify's open protocol for enabling AI agents to interact with commerce. UCP provides a standardized way for AI systems to search product catalogs, understand pricing and availability, and facilitate purchases across participating merchants. It's the infrastructure layer that makes agentic commerce possible at scale.
Learn more →Catalog Search API
Shopify's federated product search API that enables querying products across multiple stores simultaneously. Unlike the Storefront API (which queries a single store), the Catalog API aggregates product data from all participating UCP merchants. It powers the product discovery layer of agentic commerce.
Learn more →Model Context Protocol (MCP)
An open protocol for AI models to interact with external systems and tools. MCP standardizes how AI assistants connect to data sources, APIs, and services. In commerce, MCP enables AI agents to use tools like the Catalog API as part of their reasoning process, making informed product recommendations.
Semantic Search
Search that understands the meaning and intent behind queries, not just keyword matching. A semantic search for "something to keep my coffee hot" understands you want an insulated mug, even if those exact words don't appear in product titles. The Catalog API uses semantic search to improve product discovery.
Zero-Click Commerce
Purchases that happen without the user visiting a traditional storefront. In zero-click commerce, an AI agent handles product discovery, selection, and checkout facilitation entirely within a conversational interface. The user describes what they need, and the agent handles the rest.
Federated Search
Searching across multiple independent data sources with a single query. In e-commerce, federated search queries products from many different stores simultaneously. The Catalog API performs federated search across all Shopify merchants who participate in UCP.
Headless Commerce
A commerce architecture where the frontend (presentation layer) is decoupled from the backend (commerce engine). Headless allows developers to build custom shopping experiences using APIs like the Storefront API while Shopify handles inventory, payments, and fulfillment.
Product Graph
A knowledge graph of product data including relationships between products, categories, attributes, and merchants. The Catalog API draws from Shopify's product graph to understand product relationships and improve search relevance.
Shop ID
A unique identifier for a Shopify store within the UCP ecosystem. Shop IDs allow you to filter Catalog API searches to specific merchants or attribute products to their source stores.
Missing a Term?
Agentic commerce is a rapidly evolving space. If there's a term you'd like us to define, let us know.