llms.txt is a plain-text Markdown file at yoursite.com/llms.txt that gives AI tools a short map of your website: who you are, what you do and which pages matter most.
llms.txt does not help Google rankings, AI Overviews or AI Mode. Google's own guide, published 15 May 2026, says Google Search ignores it. Some AI agents and developer tools do fetch it. Creating one takes about 10 minutes, so it is worth adding for documentation-heavy or SaaS sites and is low priority for most others.
If your bigger worry is whether search engines can crawl your site at all, a technical SEO audit will tell you more than any llms.txt file.
What Is llms.txt?
llms.txt is a proposed convention, not an official web standard. Jeremy Howard published the proposal on llmstxt.org on 3 September 2024. The file sits at a domain's root and uses Markdown to give large language models a curated summary of a site, with links to its most useful pages.
The current specification (last modified 10 August 2026) sets out this order:
- An H1 with the site name, the only required element.
- A blockquote with a short summary.
- Optional paragraphs or lists that add context.
- H2 sections listing links as
[name](url): notes. - An optional section titled "Optional" for links an AI tool can skip when space is tight.
What an llms.txt File Looks Like
This is an abridged version of Bamboost's own file at bamboost.in/llms.txt:
# Bamboost
> Bamboost is an SEO and web development company in Kozhikode, Kerala.
## Services
- [SEO](https://bamboost.in/best-seo-company-in-kerala.html): Technical, on-page, local and ecommerce SEO
- [Web Development](https://bamboost.in/best-web-development-company-in-kerala.html): SEO-friendly websites and online stores
- [Google Ads](https://bamboost.in/best-google-ads-company-in-kerala.html): Campaign management for Kerala businesses
## Key Pages
- [Case Studies](https://bamboost.in/case-studies.html): Client results
- [Contact](https://bamboost.in/contact.html): Free consultation
## Optional
- [Blog](https://bamboost.in/blog.html): Guides on SEO, Google Ads and web developmentThe H1 alone makes a valid file. The blockquote is the line an AI tool is most likely to reuse, so match how you describe yourself elsewhere. Each H2 groups links with a short note, and ## Optional marks links a tool can drop.
llms.txt vs robots.txt vs sitemap.xml
| robots.txt | sitemap.xml | llms.txt | |
|---|---|---|---|
| Purpose | Tells crawlers which URLs they may fetch | Lists URLs you want discovered | Summarises your site and points AI tools to key pages |
| Who reads it | Googlebot, Bingbot, GPTBot, ClaudeBot, PerplexityBot and most crawlers | Search engines such as Google and Bing | Some AI agents, developer tools and SEO auditors; not Google Search |
| Affects rankings? | Indirectly: blocked pages can't be crawled | Helps discovery, not ranking | No, according to Google |
| Status | Formal standard (RFC 9309) | Long-established protocol | Proposal |
Our technical SEO guide explains how robots.txt and sitemaps affect crawling and indexing.
llms.txt vs llms-full.txt
llms.txt is an index of links. llms-full.txt is a companion file, generated by documentation platforms such as Mintlify, that combines an entire documentation site into one file an AI tool can load at once. It is not part of the llmstxt.org specification.
Does llms.txt Help SEO?
No, not for Google. Google Search Central's guide to generative AI features, published 15 May 2026, says Google Search does not use llms.txt, so the file neither helps nor harms rankings, AI Overviews or AI Mode.
The primary sources:
- Google Search Central, 15 May 2026. Under "Mythbusting generative AI search", Google's AI optimization guide says you don't need "machine readable files, AI text files, markup, or Markdown to appear in Google Search (including its generative AI capabilities), as Google Search itself doesn't use them."
- Google Search Central, 15 June 2026. Google added a clarification that these files "will neither harm nor help your site's visibility or rankings in Google Search, as Google Search ignores them," and that keeping one for other services is fine.
- John Mueller, Google, April 2025. In a Reddit discussion reported by Search Engine Journal, Mueller said no AI service had announced using the file and compared it to the keywords meta tag.
- Ahrefs, June 2026. An Ahrefs study of 137,210 domains found about 38,000 with a valid llms.txt file. Of those, 97% received zero requests in May 2026.
The reason is structural. Google says AI Overviews and AI Mode draw on its Search index, and a page must be indexed and eligible for a snippet to appear in them. Google may crawl /llms.txt like any file, but it doesn't treat it as special. Our guide to AI Overviews and AI Mode covers what does influence them.
Which AI Tools Actually Read llms.txt?
Very few, on public evidence. Google Search ignores it, Chrome Lighthouse checks for it, and OpenAI, Perplexity and Anthropic have made no public statement that their crawlers use it. In Ahrefs' May 2026 data, AI retrieval bots made about 1.1% of llms.txt requests.
| System | Reads llms.txt? | Source | Checked |
|---|---|---|---|
| Google Search, AI Overviews, AI Mode | No; Search ignores it | Google Search Central | 29 Oct 2026 |
| Chrome Lighthouse | Checks the file loads without a server error | Chrome for Developers | 29 Oct 2026 |
| ChatGPT (OpenAI) | No public statement; crawler docs name robots.txt | OpenAI | 29 Oct 2026 |
| Perplexity | No public statement; crawler docs name robots.txt | Perplexity | 29 Oct 2026 |
| Claude (Anthropic) | No public statement; help article names robots.txt | Claude Help Center | 29 Oct 2026 |
| AI agents and coding tools | Some fetch it; varies by tool | Ahrefs: 10.5% of requests | 29 Oct 2026 |
OpenAI and Perplexity publish llms.txt files for their own developer documentation. That is not a statement that their crawlers read yours.
The Lighthouse audit sits in the experimental Agentic Browsing category (Chrome 150 or later), which assesses how easily AI agents can use a page. A server error on /llms.txt is flagged; a missing file is marked "Not Applicable" because the file is optional. It has nothing to do with Search rankings.
Should You Add llms.txt to Your Website?
Add one if AI agents or developers use your content directly; for most other sites it is optional and low priority. It takes about 10 minutes, but an outdated file misdescribes your business, so only publish one you will maintain.
| Site type | Add llms.txt? | Why |
|---|---|---|
| Developer docs or API | Yes | Coding assistants and agents are the likeliest readers |
| SaaS product | Yes | Points agents to features, pricing and docs |
| Large ecommerce store | Optional | Can highlight key categories and policies; no effect on Google |
| Local business, clinic or institute in Kerala | Optional, low priority | Google Business Profile, reviews and indexable service pages matter far more |
| News site or blog | Optional | Agents may use it; Google Search won't |
The real risk is neglect, and we found it on our own site. When we reviewed Bamboost's file in October 2026:
- The summary was plain paragraphs, not the blockquote the specification describes.
- Seven published blog posts were missing, including our guide to ChatGPT visibility.
- Four core service pages (technical, local, on-page and off-page SEO) were not listed.
Our rankings were unaffected, but any agent relying on the file saw an incomplete picture of our services. We rewrote the summary, added the missing pages and now update the file whenever a page goes live.
Not Sure If AI Tools Can Read Your Website?
We'll check crawler access, your key pages and how AI tools describe your business.
How to Create an llms.txt File in 5 Steps
You need about 10 minutes, a text editor and access to your website's root folder.
- List the 10–20 pages that best explain your business, such as services, about, contact and your most useful guides.
- Write the file in Markdown. Save it as UTF-8 plain text named
llms.txt:# Your Business Name > What you do, for whom, and where. ## Services - [Service name](https://yoursite.com/service): One-line description ## Key Pages - [Contact](https://yoursite.com/contact): How to reach you - Upload it to your root folder. It must load at yoursite.com/llms.txt, alongside robots.txt, not in a subfolder.
- Test it. Open the URL, confirm it shows plain text and working links, then run Lighthouse in Chrome DevTools with the Agentic Browsing category and check the llms.txt audit shows no server error.
- Update it whenever you add or remove a service, and review it quarterly alongside your sitemap.
A generator can save time, but check that its output lists real, current pages.
What Actually Helps You Show Up in ChatGPT and Google AI
The work that helps regular search also drives AI visibility, and none of it depends on llms.txt.
- Crawlable, indexable pages. Google requires indexing for its AI features, and OpenAI, Perplexity and Anthropic control crawling through robots.txt. Don't block their bots by accident.
- Clear answers under question headings. Open each section with a direct, self-contained answer. Our AI search optimization guide explains the format.
- Consistent business details. Use the same name, address and phone number on your website, Google Business Profile and directories.
- Mentions on sites AI tools cite. Listings, reviews and industry articles shape how assistants describe you. See how to appear in ChatGPT results.
- Up-to-date facts and dates. Show a "last updated" date and refresh statistics when they change.
Then measure your AI search visibility each month to see what is working.