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Reference

Glossary

Every term used on this site, defined once, maintained continuously. If you find a term missing or imprecise, we want to know.

Updated : April 2026 · Primary query : agentic commerce glossary
Agent (AI)
A software system — typically built on an LLM — that perceives context, reasons over goals and takes actions, often on behalf of a human user.
Agentic commerce
Commerce flows in which AI agents participate as clients of discovery, purchase or after-sales — either advisory or transactional.
Agent-pay
Umbrella term for payment credentials and flows designed for AI agents acting on behalf of users. Examples: Stripe Agentic Commerce, Visa Intelligent Commerce, Mastercard Agent Pay.
Agent-ready catalog
A product catalog whose SKUs can be retrieved, parsed, reasoned about and acted on by an AI agent without scraping or inference.
Answer surface
An AI interface that synthesizes answers from multiple sources — e.g., ChatGPT Shopping, Perplexity Shop, Amazon Rufus, Google AI Overviews.
A2A (Agent-to-Agent)
An emerging Google-sponsored protocol for communication between AI agents, complementary to MCP.
Canonical URL
The stable, preferred URL for a resource; used by crawlers and agents to attribute retrieval.
Catalog as API
The design posture of treating a product catalog as an API surface — versioned, typed, documented — because agents consume it as such.
Commerce interoperability
The property that lets a merchant's catalog, offers and policies be understood and acted upon by any compliant agent or platform without bespoke integration.
Feed (product feed)
A structured export of a merchant's catalog, usually consumed by ad platforms, marketplaces and search engines. Google Merchant Center spec is the de facto.
GLN (Global Location Number)
A GS1 identifier for a party, location or functional entity. Used for merchant identity in supply-chain and cross-border commerce.
GS1
The international standards body behind GTIN, GLN, GPC and other identity/taxonomy systems used in commerce.
GTIN (Global Trade Item Number)
A GS1 product identifier that includes UPC, EAN-13 and ISBN. The default cross-merchant product identifier.
JSON-LD
A JSON-based format for linked structured data. The preferred way to attach schema.org markup to web pages.
llms.txt
A proposed site-level file providing guidance to LLM crawlers about content. Not commerce-specific; see the related site llmtxt.info for vertical coverage.
Machine-readable (in commerce)
Property of a catalog whose identifiers, attributes, policies, prices and availability can be consumed programmatically without scraping or inference.
MCP (Model Context Protocol)
An open protocol introduced by Anthropic (2024) for exposing tools and resources to LLM agents in a standardized way.
Merchant Center (Google)
Google's platform for ingesting merchant feeds. Its XML/CSV feed spec is the de facto standard for product data interchange.
MerchantReturnPolicy
schema.org type for structured expression of a return policy — window, cost, method, applicable countries.
Model Context Protocol
See MCP.
MPN (Manufacturer Part Number)
A manufacturer-assigned identifier, typically used in combination with Brand when GTIN is unavailable.
Offer
In schema.org, an instance of a product being sold — carrying price, currency, availability, shipping details.
Operator
An OpenAI product (2025) that drives a real browser on behalf of a user. More broadly, an emerging category: browser-use agent.
PIM (Product Information Management)
Software for managing and enriching product data centrally before syndication to channels.
Policy data
Structured expression of returns, shipping, warranty, age and geographic restrictions, subscription terms — readable by agents.
Product
In schema.org, the type describing a sold item with its attributes and offers.
Rufus (Amazon)
Amazon's in-app shopping assistant, launched 2024. An example of an embedded platform agent.
Schema.org
A vocabulary of types and properties for structured data on the web, maintained collaboratively by major search engines.
ShippingRateSettings
schema.org type for structured shipping rates, regions and delivery windows.
Sitemap
An XML file enumerating canonical URLs for crawlers, and a freshness signal.
SKU (Stock Keeping Unit)
Internal identifier for a merchant's sellable unit, typically variant-level.
Stripe Agentic Commerce (ACP)
Stripe's product suite (2024 Q4) for agent-initiated payments — scoped intents, spend controls, audit trails.
Structured data
Data described using a shared schema (e.g., schema.org) so that parsers can extract meaning without heuristics.
Substrate
In our usage: the invisible lower layers of the commerce stack on which agents and humans depend. Machine-readable by necessity.
Token (payment)
A stand-in credential representing a payment method. Agent-pay tokens are scoped, revocable and typically agent-bound.
Tool use
The pattern by which an LLM agent calls named functions (tools) to interact with external systems. Operationalized via function calling, MCP, etc.
UCP
Universal Commerce Protocol. The conceptual frame used on this site for the composite infrastructure layer making commerce agent-readable.
Universal Commerce Protocol
See UCP.
Visa Intelligent Commerce (IC)
Visa's agent-pay programme — agent-bound card credentials with delegated authority.
Variant
A specific purchasable form of a product (size, color, flavor). Should carry its own GTIN where applicable.
Webhook
A programmatic callback emitted on an event (order created, paid, shipped) — preferred over polling for lifecycle observability.

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