Understanding llm.txt: A Future Standard for AI Crawlers
The internet already has rules for search engines.
For decades, robots.txt has guided crawlers on what pages to index and what to ignore.
But with the rise of Large Language Models (LLMs) — which don’t just index content, but consume and generate from it — a new question has emerged:
How can website owners set rules for AI models?
Enter: llm.txt.
🤔 What is llm.txt?
llm.txt is a proposed standard, similar to robots.txt, that lives at the root of your website (example.com/llm.txt).
Its role is to communicate guidelines for LLMs, AI crawlers, and agents that interact with your content. Instead of focusing on search engine indexing, it covers AI-specific use cases, like training, summarization, or attribution.
🔑 Why Does It Matter?
As AI becomes part of everyday browsing and research, LLMs increasingly pull from live websites. Website owners need:
- Transparency → Decide how their content is used by AI.
- Control → Allow some use cases (like summaries) but block others (like training).
- Attribution → Require that models reference or link back to the source.
- Fairness → Help balance AI innovation with creator rights.
🛠️ How to Use llm.txt
- Create the file in the root of your domain:
[https://example.com/llm.txt](https://example.com/llm.txt)- Add your rules. A simple example:
# Allow AI to read and summarize content
Allow: summarize
# Disallow training on this website’s content
Disallow: train
# Require attribution when content is used
Attribution: required- Publish it — once the file is live, AI crawlers that follow the standard can read and respect your preferences.
📂 Example llm.txt
Here’s what a practical version might look like:
# llm.txt for ExampleSite
# AI crawlers may:
Allow: read
Allow: summarize
# But may NOT:
Disallow: train
Disallow: commercial-use
# Attribution rules
Attribution: link
Contact: [email protected]🌍 The Bigger Picture
- For creators:
llm.txtis a way to say yes to AI while keeping guardrails. - For AI developers: it reduces legal and ethical gray areas by giving clear signals.
- For the web as a whole: it’s a step toward making AI integration as standardized as SEO.
✅ Wrap-Up
Just as robots.txt became a cornerstone of the search era, llm.txt could become the standard for the AI era.
Even though adoption is still in its early stages, it’s worth keeping an eye on. If you manage a website, experimenting with llm.txt now puts you ahead of the curve.
📌 Next post: I’ll dive into possible rule sets for llm.txt and how different AI companies might interpret them.
Do you want me to also draft a forward-looking llm.txt spec (like a recommended set of fields: Allow, Disallow, Attribution, etc.), so you could include it in the post as a “proposed standard”?