- [ Home ](/) / - What is llms.txt # What is `llms.txt`? A concise definition of the proposed llms.txt convention, its current scope, measured adoption, and limits. Last updated: August 25, 2026 On this page - [ Definition ](#definition) - [ llms.txt, llmstxt, llms txt, or llmtxt? ](#spelling) - [ Origin ](#origin) - [ What problem it solves ](#what-it-solves) - [ What llms.txt is not ](#what-it-is-not) - [ Adoption status (2026) ](#adoption) - [ Typical use cases ](#use-cases) - [ Quick FAQ ](#faq) ## Definition **`llms.txt`** is a Markdown file published at a website root or a specific path. It gives compatible agents a short, curated map of useful resources under that scope. The familiar root URL is `https://example.com/llms.txt`. It was proposed by [Jeremy Howard at Answer.AI](https://www.answer.ai/posts/2024-09-03-llmstxt.html) in September 2024 as a community convention, not a formal standard. The canonical specification lives at [llmstxt.org](https://llmstxt.org/). Example One-sentence version A human-readable Markdown map, published at the root or a more specific path, that compatible clients can use to find curated resources within that scope. ## llms.txt, llmstxt, llms txt, or llmtxt? The proposed filename is **`llms.txt`**. People also search for `llmstxt`, `llms txt`, `llmtxt`, and `llm.txt` when they omit punctuation, misremember the plural, or refer to the topic rather than the literal file. Those spellings do not name separate formats. Use `llms.txt` in documentation and at the published URL. llmtxt.info is this reference site; llmstxt.org publishes the current v2 proposal. This page groups the variants instead of creating duplicate pages. ## Origin Howard’s original argument: large language models have small context windows compared to a typical website. Asking a model to crawl an entire site every time someone wants to ask a question about your product is wasteful and lossy. Sites already publish `robots.txt` for crawlers and `sitemap.xml` for search engines, `llms.txt` proposes a parallel convention specifically for LLMs. The format is intentionally minimal: - Markdown (so a human can read and edit it). - Predictable structure (so a parser can reliably extract sections and links). - Curated, not exhaustive (the goal is signal, not coverage). ## What problem it solves - **Context window limits.** Even with multi-million-token models, loading a full documentation site costs latency and money. A focused `llms.txt` can reduce unnecessary retrieval when a compatible client needs only a small set of canonical resources. - **Discovery noise.** A site’s most valuable content for an LLM is rarely the same as its most visited content. `llms.txt` lets you tell models explicitly: “these are the pages worth reading.” - **Reviewable contracts.** When the file is version-controlled and checked in CI, its URLs become an explicit surface that can be tested when pages move. - **Companion file `llms-full.txt`.** A sibling convention used by several documentation publishers inlines the content of linked pages as concatenated Markdown, so an LLM client can load a single URL and get the full, ready-to-feed corpus. ## What llms.txt is not Plenty of confusion exists in the wild. To be clear: - **It is not a W3C, IETF, or otherwise standardized protocol.** It is a community proposal. - **It is not enforced by any major LLM provider.** No vendor (OpenAI, Anthropic, Google, Meta) has publicly committed to consistently fetching it. Adoption today is mostly opportunistic. - **It is not a ranking signal.** Publishing `llms.txt` does not make your site rank higher in classic search nor in AI Overviews. There is no public evidence to that effect as of August 2026. - **It does not replace `robots.txt`, `sitemap.xml`, or schema.org.** See the dedicated [comparison page](/comparison/). - **It is not a security mechanism.** Anything you list in `llms.txt` is, by definition, public. ## Adoption status (2026) Adoption is real but uneven. Most early adopters are **documentation platforms and developer-tools companies**: Anthropic, Cloudflare, Vercel, Stripe, Mintlify, Perplexity. Outside the dev-tools world, coverage is still thin. Our fixed technology-oriented panel found 125 valid root files among 217 reachable hosts on 2026-10-05, a rate of 57.6%. This is a transparent panel measurement, not a Web-wide adoption estimate. Skepticism is also documented. Google’s John Mueller has been publicly cautious, and Mintlify themselves have [acknowledged the skepticism head-on](https://www.mintlify.com/blog/what-is-llms-txt): the file is useful as a stable, machine-readable contract, but its real-world consumption by LLMs depends on each vendor’s evolving choices. Warning Honest disclosure As of August 2026, we have no public confirmation that ChatGPT, Claude, Gemini, or Perplexity consistently fetch /llms.txt when answering user questions. Treat llms.txt as infrastructure you control , not as a guaranteed channel. ## Typical use cases - **API documentation.** Map an LLM directly to your endpoint reference pages and tutorials. - **SaaS marketing site.** Help an assistant answer questions about your product, pricing, and integrations from a small set of canonical pages. - **Open-source project.** Point clients to the README, contribution guide, examples, and changelog. - **Knowledge base.** Surface the small, high-quality answers rather than every help-center article. ## Quick FAQ **Is `llms.txt` required?** No. It is voluntary. **Will it improve my SEO?** Not directly. Read our [benefits and limitations](/benefits-limitations/) page for a careful answer. **How do I create one?** See the [step-by-step guide](/how-to-create/), or use the [generator](/generator/) to scaffold a baseline. ## Continue reading - [The llms.txt file](/llms-txt-file/), locations, scope, and discovery. - [Format reference](/llms-txt-format/), required and optional elements. - [How llms.txt works](/how-it-works/), file structure and parsing rules. - [Comparison with robots.txt and sitemap.xml](/comparison/). - [Best practices](/best-practices/), ten rules and common mistakes. ## Sources - [ llmstxt.org, community proposal ](https://llmstxt.org/) - [ Google Search Central, generative AI optimization guide ](https://developers.google.com/search/docs/fundamentals/ai-optimization-guide) - [ Answer.AI, Jeremy Howard, the original proposal (2024-09-03) ](https://www.answer.ai/posts/2024-09-03-llmstxt.html) - [ Search Engine Land, llms.txt is a treasure map for AI ](https://searchengineland.com/llms-txt-isnt-robots-txt-its-a-treasure-map-for-ai-456586) - [ Mintlify, Breaking down the skepticism ](https://www.mintlify.com/blog/what-is-llms-txt) - [ Ahrefs, 137K-site request-log study (June 2026) ](https://ahrefs.com/blog/llmstxt-study/) - [ SE Ranking, 300K-domain adoption study (June 2025) ](https://seranking.com/blog/llms-txt/)