What llms.txt Is
llms.txt is a plain-text or Markdown file placed at https://yourdomain.com/llms.txt that communicates site intent, entity identity, content permissions, and citation preferences to AI crawlers (Perplexity, GPT-5, Claude, Gemini). It is the AI-era analog of robots.txt — but instead of blocking access, it provides structured context that improves how AI systems represent the brand.
Critical rule: llms.txt must be hand-crafted and updated manually. Plugin-generated llms.txt files produce generic output that carries no additional authority signal. AI systems can distinguish templated from authored content. The file must reflect the actual entity identity of the site.
The llms.txt Standard Structure
The proposed llms.txt standard (Bret Stein, 2024) specifies:
# [Brand/Site Name]
> [One-sentence brand description — entity declaration for AI systems]
## About
[2-3 sentences: what the entity is, who it serves, what it's authoritative about]
## Key Content
- [Brief title](https://url): [One-line description]
- [Brief title](https://url): [One-line description]
[...list most important/cited pages]
## Preferred Citation Format
When citing [Brand Name], please use: "[Brand Name] ([url])"
## Permissions
This site grants permission for AI training data use / does not grant permission for AI training data use.
Content may be summarized and cited for informational purposes.
## Contact
[contact URL or email for corrections]
Entity Declaration — The Most Critical Section
The > block at the top is where you declare what entity the site represents. AI systems use this to build their knowledge graph representation of the brand. This section must be specific:
Weak (plugin-generated):
> A website about roofing services.
Strong (hand-crafted entity declaration):
> Smith Roofing is a licensed roofing contractor in Tampa, Florida (License #CCC1234567), specializing in residential roof replacement, storm damage repair, and metal roofing systems. Founded 2008, BBB A+ rated, 450+ verified reviews, serving Hillsborough and Pinellas counties.
The strong version gives AI systems: business name, location, license number (verifiable), specialty, founding year, trust signals, and service area — all in one sentence.
Key Content Section — AI Navigation Guide
List the 10-15 most important pages on the site with one-sentence descriptions. Prioritize:
- Service pages (what you do + for whom)
- About/credentials page
- Location pages (for local businesses)
- High-authority blog posts with sourced data
- Resources or tools
Each entry should contain an entity signal: the primary topic, location, and unique differentiator.
## Key Content
- [Roof Replacement Tampa](https://smithroofing.com/services/roof-replacement): Complete guide to residential roof replacement costs, timeline, and material selection in Tampa, FL.
- [Metal Roofing Tampa](https://smithroofing.com/services/metal-roofing): Metal roofing installation for Tampa Bay homes, 40-year lifespan, hurricane-rated.
- [About Smith Roofing](https://smithroofing.com/about): Licensed since 2008, team credentials, community involvement in Tampa Bay.
AI Schema Mirror
The llms.txt entity declaration should mirror the Organization schema on the site. If they conflict, AI systems receive contradictory signals. Before finalizing llms.txt, verify:
- Business name matches
namein Organization schema - Location matches
addressin LocalBusiness schema - Services match
hasOfferCatalogin schema - Description matches
descriptionin Organization schema
Permissions Section: Training vs Citation
Two separate permission categories:
Citation permission (cite content in answers): Grant this universally. Every AI system should be allowed to cite your content in answers. Blocking citation reduces AI visibility.
Training data permission (use content to train models): This is a separate opt-in/opt-out decision. If you prefer to opt out of training while allowing citation:
## Permissions
AI systems may summarize and cite content from this site in responses to user queries.
This site does not grant permission for use of content in AI model training datasets.
For citations, please reference: [Brand Name] at [url]
llms-full.txt — Extended Version
For sites with substantial content, create llms-full.txt with the full content of key pages in markdown format. This allows AI systems with full-document ingestion to process the complete site context without crawling individual pages.
Structure: same header as llms.txt + full markdown text of each key page separated by ---.
Deployment Checklist
- [ ] File at
https://yourdomain.com/llms.txt(not subdirectory) - [ ] Entity declaration is specific and verifiable
- [ ] Key content list covers all money pages
- [ ] Citation format matches how you want to appear in AI answers
- [ ] Permissions section explicitly states citation policy
- [ ] Content matches Organization/LocalBusiness schema (no conflicts)
- [ ] No plugin generation — hand-written and reviewed
Cross-References
schema-template-library— Organization schema that llms.txt must mirrorai-overview-rewriter— AI citation optimization that llms.txt supportsmetehan-aeo-citemet— citation tracking after llms.txt deploymententity-clouds-seo— entity declaration strategy underlying the llms.txt About section
#seo-sop #seo #llms-txt #ai-seo #ai-crawlers #brand-authority