Shopify llms.txt agents.md Theme Templates: Override the Defaults

Every Shopify store now serves an agent-facing file at /agents.md, and most merchants have never read theirs. Shopify generated it from store settings and pointed /llms.txt and /llms-full.txt at the same content. On 20 May 2026 the platform turned those two paths into redirects to /agents.md, killing the workarounds merchants had built in the weeks before. Eight days later the Shopify developer changelog published the supported route back: the Shopify llms.txt agents.md theme templates you drop into your theme to replace the generated output. This page covers the defaults, the three templates, what the redirect broke, which slice of a large catalogue deserves a line, and how to confirm your override is answering.

Key facts:

• Every storefront serves /agents.md, /llms.txt, /llms-full.txt and /.well-known/ucp by default, all four logged responding by No7 Software in early May 2026.
• Since 20 May 2026, /llms.txt and /llms-full.txt redirect to /agents.md, confirmed as expected by a Shopify staff reply in the developer community thread.
• The three overrides are templates/agents.md.liquid, templates/llms.txt.liquid and templates/llms-full.txt.liquid, per the Shopify developer changelog of 28 May 2026.
• A custom template replaces Shopify's output and does not merge with it, so the Storefront MCP and UCP discovery links disappear unless you copy them across.
• Adobe Analytics measured AI-referred traffic to US retail sites up 138 % year over year in May 2026, converting 54 % better than non-AI traffic across more than 1 trillion visits.

Your store already publishes these files

agents.md is the operating manual an autonomous shopping agent reads before it touches your storefront: what you sell, where the catalogue lives, which endpoints it may call, which policies apply. llms.txt is the older, narrower format, a Markdown index of the pages worth reading, proposed by Jeremy Howard, co-founder of Answer.AI, on 3 September 2024. llms-full.txt carries the content itself instead of links to it.

Shopify ships all three without asking, alongside /sitemap_agentic_discovery.xml. Honeybound's teardown of the generated default lists search, catalogue, sitemap, UCP (Universal Commerce Protocol) discovery and the Storefront MCP endpoint, the machine-readable interface an agent calls to search products and build a cart. One merchant in the Shopify Developer Community thread summarised it as "bare bones content and an Ad to sign up on Shopify."

Open that file before you change anything, because the Shopify llms.txt agents.md theme templates replace whatever is there rather than extending it. If you are still choosing between formats, settle what agents.md is actually for first.

The three Shopify llms.txt agents.md theme templates

Liquid is Shopify's server-side templating language, and the override behaves like every other theme override: add a file under templates/ through Online Store > Themes > Edit code. The changelog of 28 May 2026 names three.

Precedence between the Shopify llms.txt agents.md theme templates is fixed, and Shopify states it plainly: "If no template is present for a given path, it falls back to your agents.md template, then to the Shopify-generated default." Honeybound adds the constraint that costs merchants the most: "A custom templates/llms.txt.liquid replaces Shopify output; it does not merge with it." Copy the discovery links out of the generated file first. Liquid objects work inside these templates, so the file tracks the catalogue as it moves.

{{ shop.name | prepend: '# ' }}

> {{ shop.description | strip_html }}

## Catalogue
- [All products]({{ shop.url }}/collections/all): every product, paginated
{% for collection in collections %}
- [{{ collection.title }}]({{ shop.url }}{{ collection.url }}): {{ collection.description | strip_html | truncatewords: 18 }}
{% endfor %}

On Shopify Markets stores, No7 Software recommends branching on localization.country.iso_code and shop.currency so the file never advertises a currency the cart does not charge.

The redirect to agents.md and what it broke

The sequence is documented to the day. On 8 May 2026 merchants opened a thread in the Shopify Developer Community reporting that their customisations to /llms.txt had stopped working. On 20 May 2026, announced in that same thread at 7:49am, Shopify disabled /llms.txt and /llms-full.txt as independent documents and redirected both to /agents.md. A Shopify staff reply set the expectation: "The redirect from /llms.txt to /agents.md is expected. Shopify now uses /agents.md as the primary storefront discovery file." No changelog entry accompanied it, which is why the thread carries the primary record. Anything wired up before 20 May to serve merchant bytes at /llms.txt now competes with a platform route that answers first.

The Shopify llms.txt agents.md theme templates are the only supported customisation surface now, and templates/agents.md.liquid matters most, since it feeds all three paths until a path-specific override exists. Headless storefronts get none of it: Weaverse notes that Hydrogen has no Liquid template layer, so a headless team writes its own route returning static Markdown with a Content-Type: text/markdown header. Check how other platforms handle it before copying a template across.

What to list when the catalogue runs to thousands of SKUs

The llms.txt specification is a curation format: Jeremy Howard's original defines each section as a list "containing a required markdown hyperlink [name](url), then optionally a : and notes about the file". Weaverse states the operating rule in one line: "Keep it short, a few hundred lines of well-structured Markdown beats a 10,000-line dump that no agent will read." Six checks decide what earns a line in the Shopify llms.txt agents.md theme templates.

1. Collections over individual SKUs. A collection page carries the buying decision an agent is making; a variant page carries one price.
2. Commercial order, never alphabetical. Put the collections carrying your revenue in the first twenty lines, because agents truncate long documents.
3. The search endpoint, always. Shopify's defaults point agents at /collections/all and the /search?q={query} template, per No7 Software. Both cover every SKU you chose not to enumerate.
4. Policies, shipping and returns. Shipping windows, return terms and warranty pages answer the questions that stall an agentic checkout.
5. The discovery links Shopify put there. The Storefront MCP endpoint and the UCP profile are how an agent transacts rather than browses. Losing them to an override is a self-inflicted wound.
6. A hard line budget. Fix a ceiling of a few hundred lines and spend it deliberately.

Worked example on a 4,000 SKU store: enumerating products produces a 4,000 line file no agent reads to the end. Listing 12 revenue-carrying collections, 6 policy pages, the search endpoint and the two discovery links produces roughly 20 lines covering the same catalogue through pages an agent can traverse. The rest reaches agents through /sitemap_agentic_discovery.xml. On wording, writing the file itself is a separate discipline.

How to confirm the override is answering on your storefront

These routes are served by the published theme, so the Shopify llms.txt agents.md theme templates only take effect once that theme is live. A template sitting in an unpublished theme changes nothing an agent fetches at your domain. Shopify previews unpublished themes through shopifypreview.com share links, with preview_theme_id surviving as an unreliable legacy parameter, and shopify theme dev serves a local preview. None of the three proves what your live domain returns.

Test the primary domain instead of the .myshopify.com fallback. The first command reports status and headers, the second follows the redirect, the third prints the bytes an agent receives.

curl -sI https://yourstore.com/agents.md
curl -s -o /dev/null -w "%{http_code} %{redirect_url}\n" https://yourstore.com/llms.txt
curl -sL https://yourstore.com/agents.md | head -40

Capture the status code, the content-type header and the first body lines before publishing the theme, then run the same commands afterwards. The diff is your evidence that the template took over. For the full serving checklist, work through confirming it is served.

FAQ: Shopify llms.txt agents.md theme templates

Do the Shopify llms.txt agents.md theme templates work on Hydrogen?

No. Liquid templates only exist in Online Store themes. Weaverse's May 2026 review confirms that Hydrogen and headless storefronts need their own route handler returning a static Markdown response with a Content-Type: text/markdown header. The content brief stays identical: store description, what you sell, the endpoints an agent may call, and the support and policy surface.

Can I override /.well-known/ucp the same way?

No. No7 Software's audit is explicit that "there is no Liquid template override for this file". Shopify generates the UCP profile from store configuration, and the reasoning holds: hand-editing it would let the document claim capabilities the store does not support. Change the store settings and the profile follows automatically.

Does a custom template merge with Shopify's default content?

No. Honeybound states the rule directly: a custom templates/llms.txt.liquid replaces Shopify output and does not merge with it. The search and catalogue links, the sitemap reference, the UCP and Storefront MCP endpoints all disappear the moment your template goes live. Copy the rendered default into your template as a starting point, then edit down.

Should I keep /llms.txt now that it redirects to /agents.md?

Yes. The redirect is the platform default as of 20 May 2026, and plenty of crawlers still request /llms.txt first, since that path predates agents.md by roughly twenty months. Adding templates/llms.txt.liquid breaks the redirect for that path and serves a document of your own, which is worth doing for agents that will not follow a redirect.

How La Boétie handles the agent-facing layer

The llms.txt Generator. A researched llms.txt plus a full SEO and GEO audit, at $25 or 20 € a run, self serve, paid once, no account and no call. It reads what your domain serves today and returns a file you can paste straight into the Shopify llms.txt agents.md theme templates. Run it at laboetie.io/tools/llms-txt.

Studio builds. A team of 5 to 6 engineers ships full-stack web and commerce work across finance, insurance, legal and healthcare, from france-epargne.fr to assurecompare.fr, and every engagement leaves the client holding the code, the domain and the data.

Conclusion

Your storefront has been talking to agents since early May 2026, in words Shopify wrote for you. The Shopify llms.txt agents.md theme templates take that sentence back: templates/agents.md.liquid feeds all three paths, plus a path-specific template when one path needs its own document. Copy the discovery links out of the default before overwriting it, spend the line budget on collections and endpoints, and verify with curl against your primary domain once the theme is published. With AI-referred retail traffic up 138 % year over year in May 2026, the file earns the twenty minutes.

Sources

• Customize /llms.txt, /llms-full.txt and /agents.md : Shopify Developer Changelog, 28 May 2026
• Llms.txt and agents.md : Shopify Developer Community, May 2026
• The /llms.txt file : Jeremy Howard, Answer.AI, 3 September 2024
• Shopify llms.txt and agents.md : Honeybound, 2026
• Shopify auto-shipped /llms.txt and /agents.md : No7 Software, 2026
• Shopify theme templates, May 2026 : Weaverse, 28 May 2026
• AI-referred traffic to retail sites doubles : Digital Commerce 360, 17 June 2026
• Adding and previewing themes : Shopify Help Center, 2026

Read next:

• what agents.md is actually for
• how other platforms handle it
• writing the file itself
• confirming it is served