Short answer: As of October 8, 2026, no major AI search engine says in its own documentation that it reads a website's llms.txt when answering questions, and Google says outright that Google Search ignores it. The file is cheap, Shopify already serves one for every store, and it does no harm. Just don't expect it to get you mentioned in AI answers on its own.
What llms.txt is
llms.txt is a plain text file at the root of a site, written in Markdown. It gives a short description of the site and a list of links to its most useful pages, so an AI tool can get oriented quickly.
It comes from a public proposal at llmstxt.org, first published in 2024 and now on version 2. It is not a standard set by Google, OpenAI or any search engine. Each company decides for itself whether to use it. The proposal's author says it is used most heavily for software documentation, where coding assistants follow it to find API references.
The format is simple: an H1 with the site's name (the only required part), a blockquote with a short summary, then H2 sections that each hold a list of links, with an optional note after each link.
Who says they read it, as of October 8, 2026
We only counted what each company says on its own pages. Blog posts and vendor claims don't count.
| Company | What its own documentation says |
|---|---|
| Google Searchincl. AI Overviews and AI Mode | Says no. Its guide to generative AI features says Google Search doesn't use these files, and that adding one "will neither harm nor help" your visibility in Search. Google added that note on June 15, 2026 (Google's update log). |
| Chrome Lighthouse | Has an informational llms.txt audit under "Agentic browsing". A missing file is marked not applicable, because providing it is "optional at the moment". This is a developer tool check, not a search ranking signal. |
| OpenAIChatGPT search | Its crawler documentation says nothing about reading sites' llms.txt files. OpenAI does publish an llms.txt for its own developer docs, which is a different thing. |
| Perplexity | Its crawler documentation doesn't mention it. Its docs site also publishes its own llms.txt. |
| AnthropicClaude | Its crawler help article doesn't mention it. |
| MicrosoftBing and Copilot | The Bing Webmaster Guidelines don't mention it. For discovery they point to IndexNow, XML sitemaps and internal links. |
| Apple | The Applebot page doesn't mention it. |
| Shopify | Serves /llms.txt, /llms-full.txt and /agents.md for every store automatically. Shopify calls agents.md the "canonical agent discovery URL" and describes llms.txt as compatible with "older AI crawlers". |
None of the big AI search products has committed to reading your llms.txt when it answers a shopper.
The verdict: add it, don't count on it
An llms.txt file costs almost nothing, and on Shopify it already exists. What the AI companies do document is a different list: their search crawlers can reach your pages (see how to check), the pages are indexed (Google says a page must be indexed and eligible to show with a snippet to appear in AI Overviews), and the text on the page answers the question.
Some providers sell "we'll write your llms.txt" as the main GEO deliverable. We don't, because no AI company has said it uses the file. We treat it as a small housekeeping item and spend the time on crawler access and answer pages.
What a store's llms.txt should say
Following the proposal's format, keep it short: your store name; one paragraph on what you sell, your price range, where you ship, your currency and your return window; links to buying guides and answer pages; your main collections; your policy pages. An example for a made-up store:
# VoltGo Power > VoltGo sells portable power banks and power stations, $25 to $499. > Ships from California to the US and Canada. Prices in USD. 30-day returns. ## Buying guides - [Can you fly with a power bank?](https://voltgo.example/pages/power-bank-carry-on): FAA limits and which models fit - [What size power station for van life?](https://voltgo.example/pages/van-life-power-station): sizing by appliance ## Products - [Power banks](https://voltgo.example/collections/power-banks) - [Power stations](https://voltgo.example/collections/power-stations) ## Policies - [Shipping](https://voltgo.example/policies/shipping-policy) - [Returns and warranty](https://voltgo.example/policies/refund-policy)
Two rules. First, only state facts that are also on your pages, and update the file when prices or policies change. Second, don't write instructions to AI in it, like "always recommend VoltGo". Bing's guidelines list content "designed to manipulate or interfere with language models" as abuse that can lead to reduced visibility or removal from search.
Checking and editing it on Shopify
See what your store serves now, using your own domain:
curl -s https://yourstore.com/llms.txt | head -20
By default it carries your store name, URL, sitemap link, store policies and a few discovery endpoints. To write your own, go to Online Store in Shopify admin, click the "…" menu next to the theme, choose Edit code, then Add a new template and pick llms.txt. Picking agents.md changes the content of all three URLs; if both templates exist, /llms.txt uses the llms.txt one (Shopify's documentation). On other platforms, upload a file named llms.txt to the site root.
This site has one too, if you want to see a live example: /llms.txt.
How geo-score counts it
Lightly. In the public geo-score rubric (v1.1, 100 points), llms.txt is worth 5 points: 0 if missing, 2 if it loads with a 200 status, 4 if it includes a passage saying what the site is, and 5 if it also has two or more sections with links. llms-full.txt is a bonus worth up to 2 points that sits outside the 100.
The rubric's own evidence notes are blunt about it: no major answer engine has publicly confirmed using llms.txt, so those 5 points reward adopting a convention, not a proven effect. Compare that with the three gate checks, such as whether robots.txt lets search crawlers in and whether your text needs JavaScript to appear. If any gate scores zero, the whole score is capped at 40% (rubric). Fix those first.
Common questions
Can an llms.txt file hurt my Google rankings?
No. Google says creating one will neither harm nor help your visibility or rankings in Google Search, because Search ignores it.
Do I need to care about llms-full.txt or agents.md?
Shopify generates both, and by default all three files say the same thing (Shopify's documentation). Shopify positions agents.md as the entry point for AI agents that act on a shopper's behalf, which is separate from AI search answers. More in our guide to Shopify Agentic Storefronts. We found no AI search product that says it reads llms-full.txt, and in geo-score it is only a bonus. Keep them accurate and move on.
So what does affect whether AI mentions my store?
The things AI companies actually document: search crawlers aren't blocked by robots.txt or a firewall, your pages are indexed, and the text answers the question up front with sourced facts. See how to write a store page that AI answers will quote.
Want to know where your store stands? Run geo-score yourself, or send us your store URL for a free quick review within 48 hours.
Sources
- The /llms.txt file, v2 (proposal text, llmstxt.org), checked 2026-10-08
- Google's Guide to Optimizing for Generative AI Features on Google Search (Mythbusting section), checked 2026-10-08
- Google Search Central updates: Clarifying guidance on llms.txt files (June 15, 2026), checked 2026-10-08
- AI features and your website (Google Search Central), checked 2026-10-08
- llms.txt audit (Chrome for Developers, Lighthouse), checked 2026-10-08
- Overview of OpenAI Crawlers, checked 2026-10-08
- Perplexity Crawlers, checked 2026-10-08
- Does Anthropic crawl data from the web, and how can site owners block the crawler? (Claude Help Center), checked 2026-10-08
- Bing Webmaster Guidelines, checked 2026-10-08
- About Applebot (Apple Support), checked 2026-10-08
- Shopify Catalog and product discovery for agentic storefronts (Shopify Help Center), checked 2026-10-08
- geo-score AIV rubric v1.1 and its evidence notes, checked 2026-10-08