If you want AI assistants like ChatGPT, Claude, and Perplexity to recommend your business, you have to make it easy for them to understand what you do.
For decades, we used robots.txt to tell search engine crawlers where they were allowed to go. Today, we use a new standard to tell AI models exactly what they need to know: the llms.txt file.
If your website does not have an llms.txt file, you are forcing AI models to guess what your business is about. And when AI models have to guess, they usually cite your competitors instead.
What is an llms.txt File?
An llms.txt file is a simple, plain-text markdown file hosted at the root directory of your website (e.g., yourdomain.com/llms.txt).
Its purpose is to provide a concise, machine-readable executive summary of your website's core information. While human visitors navigate your site using menus and buttons, Large Language Models (LLMs) use the llms.txt file as a roadmap to extract facts without having to parse through heavy design elements or marketing fluff.
Why You Need an llms.txt File
When a user asks Perplexity, "What are the best accounting tools for freelance designers?", the AI engine scans the web for consensus. It looks for clear, definitive statements about features, pricing, and target audiences.
If your website is built with complex JavaScript, pop-ups, and vague copywriting, the AI crawler will struggle to extract the necessary facts. An llms.txt file solves this by serving the data on a silver platter.
By implementing this file, you:
- Reduce Hallucinations: You explicitly tell the AI what your products are, preventing it from making up incorrect features or pricing.
- Control the Narrative: You define your brand positioning, rather than letting the AI piece it together from outdated third-party directories.
- Speed Up Parsing: You give the AI a direct link to your most important canonical documentation, saving crawl budget and ensuring the most critical pages are read.
How to Write an llms.txt File
Creating the file is straightforward. It requires no complex coding, just clear, markdown-formatted text. A standard llms.txt file should include:
- The Brand Summary: A two-sentence, definitive statement of what your company does and who it serves.
- Core Offerings: A bulleted list of your main products or services.
- Key Links: Direct URLs to your pricing page, official documentation, and contact information.
- Target Audience: Explicitly state who your product is for (e.g., "Enterprise logistics companies" or "Local homeowners").
Keep the language concise and factual. Avoid promotional adjectives like "revolutionary" or "world-class." AI models prioritize verifiable facts over marketing claims.
The Foundation of Generative Engine Optimization (GEO)
Adding an llms.txt file is one of the highest-leverage technical SEO actions you can take in 2026. It is a foundational pillar of Generative Engine Optimization (GEO).
However, an llms.txt file only works if AI crawlers are actually allowed to reach your site in the first place. Many businesses inadvertently block bots like GPTBot and ClaudeBot at the server level, rendering their optimization efforts useless.
Want to know if your technical foundation is solid? Run our free audit tool to automatically check if your llms.txt is formatted correctly and if AI crawlers can access your site.