What is agents.md and what is it for in a store?

If you search for agents.md, you can run into two files that share a name and a general purpose, talking to an AI agent in Markdown, but live in different places. One is AGENTS.md, the file software teams put in their repositories so coding agents know how to work in them. The other is /agents.md, the file Shopify serves at the root of every store so shopping assistants know what it sells and how to query it. If you run a store, the second one is the one that affects you, and you probably already have it published without having written it.

What it contains

The original format is AGENTS.md, which its site describes as a README for agents: a fixed, predictable place to give a coding agent the context and instructions it needs to work on a project. It is Markdown with no required fields; it usually holds the project description, the commands to build and test, the code style and the deployment instructions. More than 60,000 open-source projects use it, tools such as OpenAI's Codex, Google's Jules, Cursor and Aider read it, and a foundation within the Linux Foundation maintains it as an open format. In a repository with several AGENTS.md files, the one closest to the file being edited wins.⁠^{[1]agents.md (Agentic AI Foundation, Linux Foundation). AGENTS.md}

Shopify took the name for something else. On a store, /agents.md is the canonical description of the store, written for agents. According to its documentation, it holds the discovery points for the UCP (Universal Commerce Protocol) and the access point for the MCP (Model Context Protocol), read-only URLs to query products, collections and searches, the store's published policies and guidance for shopping assistants such as the Shop skill.⁠^{[2]Shopify Dev Docs. agents.md.liquid} UCP is the protocol an agent uses to discover what a merchant can do: each business publishes its profile at /.well-known/ucp, and from there the agent's platform finds the access points and negotiates what it can do.⁠^{[3]ucp.dev. Universal Commerce Protocol: specification overview (2026-04-08)}

Four details on how Shopify serves it:

• It generates itself. Shopify creates a default agents.md for every store, and your own template is only needed for advanced cases the managed file does not cover.⁠^{[2]Shopify Dev Docs. agents.md.liquid}
• There is one per store, not per language. It is served on the primary domain, with no language or market prefix, and has no translated version.⁠^{[2]Shopify Dev Docs. agents.md.liquid}
• It is the reference file for two others. The /llms.txt and /llms-full.txt URLs repeat the content of /agents.md by default. If the theme has no template for one of those routes, Shopify uses the agents.md one and, if that does not exist either, the text it generates itself.⁠^{[2]Shopify Dev Docs. agents.md.liquid} Those templates can be customized since May 28, 2026.⁠^{[4]Shopify developer changelog. Customize /llms.txt, /llms-full.txt and /agents.md}
• Its template sees very little. In agents.md.liquid only two Liquid objects work, request and agents; the usual ones, such as shop or collections, do not. The agents object carries the store's name and URL, the UCP discovery URL, the MCP access point URL, the UCP versions, the currency and the XML sitemap URL.⁠^{[2]Shopify Dev Docs. agents.md.liquid}

In a store

Here is how the /agents.md of a small ceramics store might read. It is a fictional example: the store and the paths are made up, and on a real store Shopify fills in the URLs.

# Example Ceramics

> Online store for handmade stoneware ceramics, shipping to the US and Canada.
> Prices in USD.

## For shopping agents

- UCP discovery: https://example-ceramics.com/.well-known/ucp
- MCP access point: https://example-ceramics.com/example-mcp-path

## Query the catalog (read-only)

- All collections: https://example-ceramics.com/collections
- Search: https://example-ceramics.com/search?q=mug

## Policies

- Shipping, returns and privacy: https://example-ceramics.com/policies/

If you needed to change it, you would create templates/agents.md.liquid in the theme code editor, and that change would carry over to /llms.txt and /llms-full.txt as long as they have no template of their own.⁠^{[4]Shopify developer changelog. Customize /llms.txt, /llms-full.txt and /agents.md} A minimal version that only uses the data Shopify makes available to that template:⁠^{[2]Shopify Dev Docs. agents.md.liquid}

# {{ agents.store_name }}

Online store for handmade stoneware ceramics. Prices in {{ agents.currency }}.

- UCP discovery: {{ agents.ucp_discovery_url }}
- MCP access point: {{ agents.mcp_endpoint_url }}
- Sitemap: {{ agents.sitemap_url }}

Before publishing something like this, a warning from Shopify itself: the file is public and cached, so it must not carry the merchant's private data, such as a contact email or phone number.⁠^{[2]Shopify Dev Docs. agents.md.liquid}

How to check

1. Open yourdomain.com/agents.md in the browser. If your store is on Shopify, you will see the file the platform generates or the one from your theme.⁠^{[2]Shopify Dev Docs. agents.md.liquid}
2. Also open /llms.txt and /llms-full.txt and compare them. If they are identical, it is normal that none has a template of its own and all three come from the same source.⁠^{[2]Shopify Dev Docs. agents.md.liquid}
3. Check in the theme code editor whether templates/agents.md.liquid exists. If it does, someone customized it, and that text also rules on the routes that have no template of their own.⁠^{[4]Shopify developer changelog. Customize /llms.txt, /llms-full.txt and /agents.md}
4. Look for data that should not be there: a personal email, a phone number, a test URL.⁠^{[2]Shopify Dev Docs. agents.md.liquid}
5. Open every link in the file and check that it responds. An agent that reaches a broken route has nobody to ask.

Related concept: llms.txt

The llms.txt file is a proposal by Jeremy Howard, from September 2024, to give language models a Markdown file with a curated, easy-to-use view of the site when they answer.⁠^{[6]llmstxt.org (Jeremy Howard). The /llms.txt file} On Shopify the two files overlap: by default, /llms.txt repeats the content of /agents.md, and they only separate if the theme has an llms.txt.liquid template.⁠^{[2]Shopify Dev Docs. agents.md.liquid} The difference lies in the intended reader. llms.txt is a general reading guide; Shopify's /agents.md, according to its documentation, is meant for agents and shopping assistants that need to discover the store and know how to buy from it, with UCP and MCP as entry points.⁠^{[2]Shopify Dev Docs. agents.md.liquid}

To go further, the llms.txt entry covers what Google has said about those files, and the reading path for this topic lays out the rest of the terms.