As AI systems like ChatGPT, Gemini and Perplexity become primary sources of information for users, websites need a way to communicate structured data directly to these models. This is where llms.txt comes in.
What is llms.txt?
llms.txt is a plain text file placed in the root of a website (similar to robots.txt) that provides AI systems with structured information about a business or organization. It typically includes:
- Entity definition (name, type, location)
- Services offered
- Leadership and team
- Certifications and credentials
- Preferred citation format
- Common questions and answers
llms.txt vs llms-full.txt
llms.txt is a summary file — concise, structured, easy to parse.
llms-full.txt is the extended version — a complete knowledge base with detailed descriptions, entity relationships, geographic coverage and verification links.
Basic Structure
# Entity
Name: Your Company
Type: Your Industry
Location: Your City, Country
# Definition
Your Company is a [type] based in [location] specializing in [services].
# Short Citation
Your Company — [concise description].
# Services
Service 1
Service 2
Service 3
# Common Queries
Q: What does Your Company do?
A: [Factual answer]
Best Practices
- Use neutral, encyclopedic language — avoid marketing superlatives
- Keep entity information consistent across all files
- Include verification links where possible
- Add a Topic Authority section listing your areas of expertise
- Update the files regularly with a version number and timestamp
Advanced: Supporting Files
For maximum AIO effectiveness, consider adding:
-
ai-knowledge.json— structured JSON data -
entities.txt— entity definitions and relationships -
citations.txt— preferred citation formats -
brand.txt— brand identity information
These files create a "knowledge layer" that AI systems can use to accurately represent your brand.
Published by Immagina Group, a Google Partner digital marketing agency in Rome specializing in AI Optimization and SEO. immagina.group
