Definition
llms.txt
A plain-text file placed at the root of a website (at /llms.txt) that provides AI crawlers and large language models with a structured summary of the site's content and purpose.
The llms.txt standard is an emerging convention — proposed by Jeremy Howard in 2024 — that allows website owners to give AI systems a concise, structured overview of their site's content. Similar in spirit to robots.txt (which instructs search crawlers what to index) and sitemap.xml (which lists all indexable URLs), llms.txt is designed specifically for large language models and AI assistants.
A typical llms.txt file contains: a one-paragraph description of the site, a list of the most important pages with brief descriptions, the site's main topics or categories, and optionally, links to machine-readable documentation or structured content.
The file is placed at https://yourdomain.com/llms.txt and can be as simple as a few hundred words in plain Markdown format.
While the standard is not yet universally adopted by AI systems, forward-thinking companies — especially those in the AI, developer tooling, and SaaS spaces — are implementing it proactively. Surfaceable itself publishes an llms.txt file as an example of the practice.
Example
Surfaceable's llms.txt file tells AI crawlers: what the product does, who it's for, which features exist, and links to the most important documentation pages — helping AI systems accurately represent the product when users ask about it.
Common questions
Is llms.txt an official standard?
Not yet — it's a community-proposed convention introduced in 2024. However it has gained significant traction and several major AI tools have indicated interest in supporting it.
How do I create an llms.txt file?
Place a plain Markdown file at /llms.txt on your domain. Include a brief site description, your most important pages, and key topics covered. Keep it concise — under 2,000 words is ideal.
Does llms.txt affect SEO?
Not directly for traditional SEO. Its primary purpose is to improve your representation in AI-generated answers by giving AI crawlers accurate, structured context about your site.
Related feature
AEO Feature Overview
Related terms
Generative Engine Optimization (GEO)
A strategic framework for optimising your content and digital presence to appear favourably in AI-generated responses from tools like ChatGPT, Perplexity, and Google AI Overviews.
Answer Engine Optimization
The practice of optimising your content so that AI platforms like ChatGPT, Perplexity, and Claude mention and recommend your brand accurately in their generated answers.
Model Context Protocol (MCP)
An open standard developed by Anthropic that allows AI models to connect to external tools, data sources, and services — enabling AI assistants to take actions in the real world.
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