Definition
What is llms.txt?
llms.txt is an emerging standard for providing AI engines with structured brand information. Placed at the root of a website (e.g., example.com/llms.txt), it contains a concise, machine-readable summary of what the brand is, what it does, and how it should be referenced by AI systems.
The file typically includes: brand name and entity type, primary offerings and services, key differentiators, preferred citation formats, links to detailed pages, and factual claims that AI models can confidently attribute to the brand. The format is designed to be simple enough for any AI crawler to parse while providing rich enough information to influence how AI engines describe the brand.
llms.txt works alongside related files like llm-profile.json (a JSON-LD structured version) and the .well-known/ai.txt file (which contains crawler directives and expertise signals). Together, these files form the AI indexing surface of a website—the layer of content specifically designed for AI consumption rather than human browsing.
Adoption of llms.txt is growing rapidly as brands recognise that AI engines are a primary discovery channel. Just as robots.txt became essential for SEO, llms.txt is becoming essential for AEO. Brands that implement it early gain a structural advantage in how AI engines understand and represent them.
Why it matters
llms.txt gives brands direct influence over how AI engines understand and describe their offerings. Without it, AI engines rely on scraped web content and training data associations, which may be outdated, inaccurate, or incomplete. With llms.txt, brands provide a canonical source of truth that AI crawlers can reference when generating brand-related responses.
Real-world examples
- 1
A SaaS company's llms.txt listing their products, features, and preferred citation format
- 2
An ecommerce brand using llms.txt to specify their market position and unique value propositions
- 3
A consulting firm's llms.txt providing expertise areas and advisory role descriptions
Frequently asked questions about llms.txt
Explore related concepts
llm-profile.json
technicalllm-profile.json is a JSON-LD structured data file placed at .well-known/llm-profile.json that provides machine-readable brand identity, offerings, expertise, and preferred citation formats to AI crawlers and language models.
AI Crawlers
technicalAI Crawlers are automated bots operated by AI companies that scan websites to collect content for training data and real-time retrieval. Major AI crawlers include GPTBot (OpenAI), ClaudeBot (Anthropic), PerplexityBot (Perplexity), Google-Extended (Google), and Bingbot (Microsoft).
Technical AEO
technicalTechnical AEO encompasses the infrastructure and technical configurations that help AI engines discover, crawl, parse, and cite your content. It includes AI-specific crawl policies, structured data implementation, llms.txt files, site architecture optimisation, and content formatting for AI consumption.
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