llms.txt
A proposed convention, published by Jeremy Howard in September 2024, for a Markdown file at a site's root that tells language models what the site is and where to read more.
- Proposed
- 2024-09
Connected
Linked from
- Markdown (.md)A plain-text formatting syntax that renders to HTML; the default format for agent instructions, plans and READMEs because it is cheap to generate, easy to diff and readable unrendered.
- Content Credentials (C2PA)An open standard from the Coalition for Content Provenance and Authenticity for attaching signed provenance information to media files.
- Schema.orgA shared vocabulary for structured data, founded in 2011 by Google, Microsoft, Yahoo and Yandex, that search engines and AI systems use to understand pages.
- AI search visibility (AEO / GEO)Making a business understandable and citable by AI answer engines.
Field notes that cover llms.txt
More agent tooling & protocols
- Claude CodeAnthropic's agentic coding tool that reads a codebase, edits files, runs commands and verifies its work from the terminal, IDE or web.
- agent-html-kitAn open-source template kit and Claude Code skill (kit.js) that lets agents emit content-only HTML components while design lives in one shared file, published with a 72-run HTML vs Markdown benchmark.
- CLAUDE.mdA Markdown file of standing instructions that Claude Code loads at the start of every session, at user, project and folder level.
- Karpathy-inspired CLAUDE.md rulesA widely starred public CLAUDE.md with four behaviour rules: think before coding, simplicity first, surgical changes and goal-driven execution.
- AGENTS.mdAn open, tool-neutral Markdown convention for giving coding agents project instructions, introduced by OpenAI in August 2025 and now stewarded by the Linux Foundation's Agentic AI Foundation.
- Claude Code hooksShell commands that Claude Code runs automatically at lifecycle events such as before or after a tool call, so rules can be enforced by code rather than requested in prose.