The canonical definition of AI Visibility Checking and related terminology for how websites communicate with AI systems.
Canonical URL: https://www.365i.co.uk/ai-visibility-definition/
Published by 365i
AI Visibility Checking is the process of technically verifying whether a website can be correctly discovered, interpreted, trusted, and safely used by AI systems such as ChatGPT, Claude, Gemini, and other large language models.
It focuses on infrastructure, clarity, and machine-readable identity - not popularity, rankings, or brand mentions.
This repository contains:
| File | Purpose |
|---|---|
| ai-visibility-definition.json | Canonical definitions in JSON format |
| ai-visibility-definition.yaml | Canonical definitions in YAML format |
The human-readable website at 365i.co.uk/ai-visibility-definition/ is built with PHP:
index.php # Main definition page
css/style.css # External stylesheet
js/ # Search functionality
includes/ # Shared PHP components
├── header.php # Page head and opening body
├── footer.php # Page footer and closing body
├── nav.php # Main navigation
├── sidebar.php # Specification sidebar
├── breadcrumbs.php # Breadcrumb component
├── schema.php # JSON-LD schema helpers
└── versions.php # Centralised version configuration
specifications/ # AI Discovery File specifications
├── index.php # Specifications hub
├── llms-txt/index.php # llms.txt specification (ADF-001)
├── llm-txt/index.php # llm.txt specification (ADF-002)
├── llms-html/index.php # llms.html specification (ADF-003)
├── ai-txt/index.php # ai.txt specification (ADF-004)
├── ai-json/index.php # ai.json specification (ADF-005)
├── identity-json/index.php # identity.json specification (ADF-006)
├── brand-txt/index.php # brand.txt specification (ADF-007)
├── faq-ai-txt/index.php # faq-ai.txt specification (ADF-008)
├── developer-ai-txt/index.php # developer-ai.txt specification (ADF-009)
├── robots-ai-txt/index.php # robots-ai.txt specification (ADF-010)
├── quick-start/index.php # Quick Start implementation guide
├── interoperability/index.php # Conflict resolution & precedence guide
├── validation/index.php # Test prompts & scoring framework
└── examples/index.php # Example files
This repository contains PHP source files. GitHub does not render PHP, so the files here are for:
- Version control of the canonical definitions
- Source code for the 365i.co.uk implementation
- Machine-readable formats (JSON/YAML) that can be used directly
The canonical, browsable website is at: https://www.365i.co.uk/ai-visibility-definition/
| Code | Term |
|---|---|
| AV-001 | AI Visibility |
| AV-002 | AI Visibility Checking |
| AV-003 | AI Discovery Files |
| AV-004 | AI Visibility Tracking |
| AV-005 | AI Visibility Monitoring |
| AV-006 | AI Retrieval Testing |
| Code | File | Purpose |
|---|---|---|
| ADF-001 | llms.txt | Core AI-readable business identity |
| ADF-002 | llm.txt | Compatibility variant (redirects to llms.txt) |
| ADF-003 | llms.html | Human-readable presentation with Schema.org |
| ADF-004 | ai.txt | AI usage permissions and restrictions |
| ADF-005 | ai.json | Machine-parseable AI interaction guidance |
| ADF-006 | identity.json | Canonical structured identity data |
| ADF-007 | brand.txt | Brand naming conventions |
| ADF-008 | faq-ai.txt | AI-optimised Q&A content |
| ADF-009 | developer-ai.txt | Technical context for integrations |
| ADF-010 | robots-ai.txt | AI crawler-specific access directives |
Current version: 1.3.2 (2026-01-16)
See CHANGELOG.md for version history.
A draft ETSI Technical Specification is available in the outputs/ folder:
| File | Description |
|---|---|
| ETSI-TS-AI-Visibility-v1.0.0.md | Markdown format |
| ETSI-TS-AI-Visibility-v1.0.0.docx | Word format |
The 365i AI Visibility Checker is the reference implementation of these definitions.
The website includes comprehensive Schema.org structured data:
DefinedTermandDefinedTermSetfor terminologyTechArticlefor specification pagesFAQPagefor frequently asked questionsBreadcrumbListfor navigationOrganizationfor publisher information
This work is licensed under Creative Commons Attribution 4.0 International (CC-BY-4.0).
- AI Visibility Definition - Canonical URL
- AI Visibility Checker - Reference tool
- 365i - Publisher