The Agentic Commerce Glossary

Agentic commerce arrived fast and brought its own vocabulary with it. Merchants and agency teams now have to hold apart terms that sound similar but mean different things — a Brand Agent is not a chatbot, TACOS is not ACOS, and "structured data" means something specific, not just "organized information." This glossary defines the ~40 terms you'll actually run into, grouped by category, one sentence each. No essay between entries — the definitions do the work.

Platform & products

The named products and platform features you'll encounter across Shopify, Amazon, and the major AI assistants.

Agentic commerce

Commerce transactions initiated, researched, or completed with an AI agent acting on the shopper's behalf, rather than a human clicking through a storefront unassisted.

The longer explanation, with how an agent moves from discovery to checkout and which protocols sit underneath, is in what agentic commerce is, in plain English.

Brand Agent

Microsoft's AI shopping agent for a merchant's own storefront, announced in January 2026 and installed through Microsoft Clarity plus Microsoft's waitlist — not a Shopify feature, and not limited to Shopify Plus. Brand Agents was in beta as of Microsoft's July 2026 documentation, for Shopify and WooCommerce sites.

Copilot Checkout

Microsoft's checkout inside Microsoft Copilot, announced in January 2026 — a Microsoft product, not a Shopify one; for Shopify merchants it runs on Shopify's direct checkout, and the order books into the merchant's store like any other.

Shopify Catalog

Shopify's standardized, enriched dataset of eligible merchants' products, made available to AI channels; eligibility starts at the Starter plan.

Universal Commerce Protocol (UCP)

The open standard behind Shopify's Catalog, Cart and Checkout MCPs, which lets AI surfaces such as Microsoft Copilot complete purchases inside a conversation.

Agentic storefronts

Shopify's way of selling inside AI channels such as ChatGPT, Microsoft Copilot and Google AI Mode — active by default for eligible stores and managed under Sales channels → Agentic.

Agentic plan

A Shopify plan for businesses not using Shopify as their storefront, letting them sync products to Shopify Catalog and sell in AI channels; announced in Shopify's Spring '26 Edition (check Shopify for current availability and pricing).

Alexa for Shopping (formerly Rufus)

Amazon's built-in AI shopping assistant, renamed from Rufus on May 13, 2026, which answers product questions directly inside the Amazon app and site using Amazon's own catalog and review data.

Off-site assistant

An AI assistant that recommends or discusses products outside the merchant's own storefront — ChatGPT, Claude, Gemini, and Perplexity are the primary examples merchants optimize for.

Google AI Overviews

AI-generated summary panels shown above traditional results in Google Search, which can cite and link to product pages the way a human-written snippet used to.

Shopify Plus

Shopify's enterprise tier, with the fullest checkout extensibility, unlimited and company-specific B2B catalogs and multi-store tools — not a requirement for Brand Agents, Copilot Checkout, Shopify Catalog or agentic storefronts.

Conversation design

The deliberate scripting of how a Brand Agent greets, questions, and guides a shopper — tone, fallback behavior, and escalation paths, not just the product answers underneath.

Merchandising agent

An AI system that actively curates, bundles, or recommends products on a merchant's behalf, going beyond answering questions into making merchandising decisions.

Agentic Commerce Setup

GigaCommerce's flagship engagement: a fixed-scope implementation that gets a merchant's Brand Agent, catalog data, and checkout configuration live within two weeks.

Catalog & data

The product-data concepts that determine whether an agent can actually answer a shopper's question.

Structured attribute

A named, machine-readable field with a discrete value — material: leather, sleeve_length: short — as opposed to the same fact buried in a marketing sentence.

Catalog enrichment

The process of extracting facts trapped in product-description prose and turning them into structured fields an agent can query directly.

PIM

Product information management system — dedicated software for managing product data at scale, as distinct from using a platform's native fields for the same purpose.

Shopify metafield

A custom structured field on a Shopify product, collection, or variant — the mechanism most mid-market merchants use to add attributes without a separate PIM.

Compatibility data

Structured "works with" or "fits" relationships between products, which agents rely on heavily because shoppers frequently ask compatibility questions by exact model or part.

Product taxonomy

The hierarchical category structure a catalog is organized under, which agents use to scope what "kind" of product they're reasoning about before checking specific attributes.

Attribute coverage

The percentage of SKUs in a category that have a given structured field populated — the core metric for measuring how enriched a catalog actually is.

Catalog debt

The accumulated backlog of missing, inconsistent, or prose-trapped product data that silently degrades agent accuracy and AI search visibility over time.

Variant data

Structured attributes at the size, color, or configuration level rather than the parent product level — a common gap since many catalogs enrich the parent and leave variants blank.

Backend attribute (Amazon)

Amazon search terms and fields that aren't shown on the listing but still feed indexing and, increasingly, Alexa for Shopping's ability to answer questions about the product.

GEO & AI search

The discipline of getting cited and recommended by AI assistants, as distinct from ranking in traditional search.

Commerce GEO

Generative engine optimization applied to commerce — the practice of structuring a catalog and content so AI assistants like ChatGPT, Claude, Gemini, and Perplexity cite and recommend it.

GEO vs SEO

SEO optimizes for ranking in a list of links; GEO optimizes for being the fact or product an AI assistant quotes or recommends directly, often without a click-through at all.

Citation

An instance of an AI assistant referencing or recommending a specific merchant, product, or piece of content in its response to a user query.

Citation rate

The share of relevant queries in which a given assistant cites or recommends a merchant's products — the core benchmark metric for Commerce GEO work.

llms.txt

A proposed plain-text file at a site's root that summarizes what the site offers, aimed at giving AI crawlers a fast, structured entry point similar to robots.txt for search crawlers.

AI crawler

A bot operated by an AI company (OpenAI, Anthropic, Google, Perplexity, and others) that fetches web content specifically to train models or answer live user queries.

Structured data (schema.org)

Markup embedded in a page, such as Product or FAQPage schema, that tells both search engines and AI assistants exactly what a piece of content is, rather than making them infer it.

Corroboration graph

The network of independent mentions, reviews, and citations of a product across the web that AI assistants use as a trust signal before recommending it.

Quotable content

Content written in short, self-contained, fact-dense sentences specifically because that shape is what AI assistants can lift cleanly into a generated answer.

AI Citation Check

GigaCommerce's free tool that tests whether AI assistants currently cite or recommend a given merchant's products for its own core queries.

Amazon-specific

Terms specific to selling and measuring performance on Amazon now that shoppers ask Alexa for Shopping.

TACOS

Total advertising cost of sale — ad spend divided by total revenue (ad-attributed and organic combined) — the measurement Amazon sellers shift to once AI-influenced sales grow outside ad attribution.

ACOS

Advertising cost of sale — ad spend divided by ad-attributed revenue only — the older metric that understates efficiency once Alexa for Shopping and off-site assistants drive organic-looking sales.

The Rufus test

A practical check, named before Amazon renamed the assistant, where a seller asks Alexa for Shopping the exact questions a shopper would about their listing, to see whether the assistant can answer accurately from the current product data.

A+ Content

Amazon's enhanced brand content module on a listing, which increasingly needs to carry structured, factual detail because Alexa for Shopping draws on it when answering shopper questions.

Browse tree

Amazon's internal category hierarchy that a listing is filed under, which determines what filters and comparisons a listing is eligible to appear in.

SPAG PPC structure

Single-product ad group structure, in which each ad group advertises exactly one product — the standard architecture for keeping Amazon PPC data clean enough to act on.

Measurement & delivery

How agencies and merchants track whether agentic-commerce work is actually paying off.

Agentic Commerce Readiness Score

GigaCommerce's free 100-point, three-minute assessment that grades a merchant's catalog, structured data, and checkout readiness for Brand Agents and AI search.

Readiness checklist

The step-by-step audit a merchant or agency runs through — catalog, structured data, checkout, and content — before flipping on a Brand Agent in production.

QBR (agentic engagement)

A quarterly business review structured around agentic-commerce metrics specifically — citation rate, agent accuracy, TACOS — rather than generic traffic and conversion reporting.

White-label delivery

An arrangement where an agency sells agentic-commerce work under its own brand while a partner like GigaCommerce delivers the implementation behind the scenes.

Rule of thumb

How GigaCommerce labels a working heuristic from its own delivery work — a number we use to decide where to start, stated as such, never presented as a measured statistic.

How to use this glossary

Treat this as a working reference, not a one-time read. When a client or teammate uses a term loosely — "can we get a chatbot like Brand Agents" or "our ACOS looks great" — the precise definition is usually the fastest way to correct the assumption underneath it. Two examples worth internalizing:

• "What is a Brand Agent?" It is Microsoft's AI shopping agent for a merchant's own storefront, announced in January 2026 and installed through Microsoft Clarity — not a scripted chatbot, and not limited to Shopify Plus.
• "What is TACOS?" Total advertising cost of sale divides ad spend by total revenue, ad-attributed and organic combined — the metric Amazon sellers increasingly rely on because Alexa for Shopping and off-site assistants like ChatGPT drive sales that ad-attribution models never see.

Where to go deeper

This glossary is deliberately flat — one sentence per term, no argument. For the fuller picture behind any category, start with the Shopify agentic commerce 2026 guide for platform terms, or what gets products recommended by AI for the GEO terms. If you want to know where your own catalog and setup stand against these terms in practice, the readiness checklist walks through it step by step.

If a term here describes a gap rather than a capability you already have — no compatibility data, no llms.txt, no measured citation rate — that gap is usually the highest-leverage place to start. Catalog enrichment and Commerce GEO are the two GigaCommerce services built specifically to close those gaps.