llms.txt Generator
Build a spec-correct llms.txt — the Markdown site guide AI systems read first — with a live preview, format linting, and a matching robots.txt AI policy from the bundled crawler registry. 100% in-browser, nothing uploaded.
# Site name
Honest framing: llms.txt is an emerging convention (llmstxt.org) and a positive signal that helps AI systems find your best content — it is not access control, and adoption is still evolving. robots.txt remains the gatekeeper. Serve this file at /llms.txt in UTF-8.
Match llms.txt with an AI crawler policy
# AI policy: visible in AI search, opted out of model training User-agent: OAI-SearchBot Allow: / User-agent: Claude-SearchBot Allow: / User-agent: PerplexityBot Allow: / User-agent: DuckAssistBot Allow: / User-agent: GPTBot Disallow: / User-agent: ClaudeBot Disallow: / User-agent: Google-Extended Disallow: / User-agent: Google-CloudVertexBot Disallow: / User-agent: Applebot-Extended Disallow: / User-agent: CCBot Disallow: / User-agent: Meta-ExternalAgent Disallow: / User-agent: Bytespider Disallow: / User-agent: Amazonbot Disallow: / User-agent: anthropic-ai Disallow: / User-agent: Claude-Web Disallow: / # Note: robots.txt is a request, not enforcement. Bytespider often ignores it — # use server/WAF rules for hard blocks.
| Operator | User-agent | Purpose | robots.txt |
|---|---|---|---|
| OpenAI | GPTBot | training | honors |
| OpenAI | OAI-SearchBot | AI search | honors |
| OpenAI | ChatGPT-User | user-triggered | honors |
| Anthropic | ClaudeBot | training | honors |
| Anthropic | Claude-SearchBot | AI search | honors |
| Anthropic | Claude-User | user-triggered | honors |
| Perplexity | PerplexityBot | AI search | declared |
| Perplexity | Perplexity-User | user-triggered | mixed history |
| Google-Extended | training | honors | |
| Google-CloudVertexBot | training | honors | |
| Apple | Applebot-Extended | training | honors |
| Common Crawl | CCBot | training | mixed history |
| Meta | Meta-ExternalAgent | training | declared |
| Meta | Meta-ExternalFetcher | user-triggered | declared |
| ByteDance | Bytespider | training | often ignores |
| Amazon | Amazonbot | training | honors |
| DuckDuckGo | DuckAssistBot | AI search | honors |
| Mistral | MistralAI-User | user-triggered | declared |
The full registry with one-click Allow/Block editing lives in the Robots.txt Studio.
The llms.txt format
Exactly one H1 line with the site or project name. It is the only mandatory element in the spec.
A one-paragraph summary right under the H1 — the first (sometimes only) thing a model ingests. Make it count.
Markdown H2 sections containing "- [title](url): note" lines. Curate your best pages — this is a guide, not a sitemap.
A specially-named last section models may skip when context is short. Put nice-to-have links here, never essentials.
Why a Markdown file for machines is suddenly worth writing
llms.txt exists because language models read the web under a constraint browsers never had: a context window. A crawler indexing your site can afford to parse every page; an AI assistant answering a question about your product often gets one shot at a few thousand tokens. The llmstxt.org proposal answers that with a curated, plain-Markdown guide at /llms.txt — one H1, a blockquote summary, and sections of annotated links pointing at your genuinely important pages. It is the difference between handing a visitor your site and handing them a well-written index card about it.
The craft is in curation, not completeness. A sitemap enumerates everything; llms.txt should name the ten to thirty pages that actually explain you — quickstart, concepts, pricing, API reference, security page — each with a note that tells the model why it would follow that link. The blockquote summary deserves the most attention: write it like the answer you would want an assistant to give when someone asks “what is this site?”. The spec's ## Optional section is a clever pressure valve — models are told they may skip it when context is tight, so it is exactly where changelogs and press pages belong.
Stay honest about what the file does. It is a positive signal, not a control surface: it invites and orients AI systems that choose to read it, while robots.txt remains the mechanism that grants or denies access, crawler by crawler. Adoption is real but still evolving — some assistants fetch it eagerly, others not yet — which is why the smart move is pairing: publish llms.txt for the systems you welcome, and set an explicit AI-crawler policy for the rest. The policy panel above generates that robots.txt block from the same registry the Robots.txt Studio uses, so the two files never contradict each other.
Treat llms.txt as living documentation: regenerate it when your docs move, keep URLs absolute, serve it as UTF-8 plain text, and let the linter here catch format drift (a missing H1 or a malformed link line makes the file useless to parsers). Then round out the machine-readable layer of your site — validate your structured data in the Schema Studio, keep the sitemap fresh, and audit the pages you are pointing models at with SEO Audit Pro.
Trusted for AI-Era Publishing
“We shipped llms.txt for our docs site in twenty minutes with this. The Optional-section semantics were the thing nobody on the team knew about — the reference cards taught us the spec while we filled the form. Lint caught a malformed link line that would have broken parsers.”
“The pairing panel is the smart part: llms.txt for guidance plus the 'search-visible, no training' robots block from the same registry. Our AI policy went from a vague TODO to two shipped files in one sitting. Honest framing throughout — no snake-oil ranking promises.”
“I rewrote our blockquote summary three times using their 'paste it into an assistant and see what it says' test — the final version now shows up nearly verbatim when people ask ChatGPT about us. That one paragraph was worth the whole exercise.”
“Clean generator, correct format, sensible lint. I'd love a bulk importer from an existing sitemap someday, but honestly the manual curation is the point — the file came out tight and our AI-search citations improved within weeks. The crawler registry table is my new reference.”
Love using our calculator?
More of SEO Forge
Similar Calculators
More tools in the same category
SEO Audit Pro
Paste HTML or fetch a live URL and get a unified 85-check audit — on-page, technical, content, links, images, structured data and security — with weighted scores, a fix-first list and JSON/CSV/Markdown export.
SERP & Social Preview
Pixel-accurate Google SERP preview (desktop + mobile, canvas-measured Arial with query bolding) plus Facebook, X, LinkedIn, WhatsApp and Discord card mockups.
Meta Tags Studio
Build a complete, correct <head>: title and description with live character + pixel meters, canonical, robots directives, Open Graph and Twitter cards — copy one clean block.
Keyword Density & N-Grams
Exact keyword density, a placement matrix (title, H1, first 100 words, URL, alts), keyword proximity, 1–4-gram tables and top-word analysis — computed, not guessed.
Readability Scorer
All seven readability formulas — Flesch, Flesch–Kincaid, Gunning Fog, SMOG, Coleman–Liau, ARI, Dale–Chall — computed from first principles with per-sentence highlighting.
Robots.txt Studio
Generate robots.txt with AI-crawler policy presets (GPTBot, ClaudeBot, CCBot…) and test any URL against any file with RFC 9309 longest-match semantics — winning line highlighted.
Often Used Together
Complementary tools for complete analysis
Related Articles
Dive deeper with our expert guides and tutorials related to llms.txt Generator
llmstxt.org format · live preview + lint · Optional section · AI-crawler policy pairing · in-browser · Last reviewed: 2026-07