TL;DR: /llms.txt is a plain Markdown file at the root of your site that summarizes what your site is, what you offer, and where the most important content lives. Think robots.txt for AI crawlers, with a different purpose: not what to crawl, but what to make of what is crawled. Adoption is uneven, the convention is not yet a standard, and the upside is uncertain but real for sites trying to win AI search citation. Cost to add: roughly an hour. Include: site purpose, services or products with prices, links to canonical pages, optional structured context. Skip: marketing copy, full content dumps, anything that changes weekly.
/llms.txt is a small file at the root of your site that tells AI search engines and LLM-powered tools what your site is about, in a format they can read efficiently. Think of it as robots.txt for AI crawlers, with a different purpose: not "what you can crawl," but "what to make of what you crawl."
It's a convention, not a standard. Adoption is uneven. The cost to add one is roughly an hour, and the upside, while uncertain, is real for sites trying to win on AI search citation.
Here's what to put in one and what to skip.
What it actually is
A plain Markdown file at https://yoursite.com/llms.txt that summarizes:
- What your site is.
- What you offer.
- Where the most important content lives (with links).
- Optional structured context (services, prices, locations).
It's read by AI crawlers and LLM tools that are increasingly looking for compact, structured representations of a site without having to crawl 200 pages.
Why it might matter
Two reasons.
1. AI search citation efficiency. Tools like Perplexity, ChatGPT browsing, and Claude's web tools look at sites quickly. A clean /llms.txt lets them grasp your site in 2 seconds instead of 30, which can affect whether you get cited.
2. Inference-time tool use. Some agentic tools fetch /llms.txt when deciding whether to read your site at all. A good one earns a deeper read.
The downside: nobody's measured the lift cleanly because adoption is still early. Treat it as cheap infrastructure, not as a primary SEO play.
The format (as it stands)
There's no formal spec yet. The convention as of mid-2026 is:
# [Site Name]
> [One-line description of what the site is]
## About
[2–3 paragraphs on what the company does, who it's for, what makes it specific.]
## Services / Offerings
- [Service 1]: [one-line description]
- [Service 2]: [one-line description]
## Important pages
- [Homepage](/): [what it covers]
- [Services](/services): [what it covers]
- [About](/about): [what it covers]
## Pricing
[Plain language about pricing structure, ranges, or links to pricing.]
## Optional sections
[Locations, team, FAQ summary, contact info, anything else worth indexing.]
This is the rough shape. Treat it as a structured pitch deck written for an LLM.
A real example
Here's roughly what Webdimonia's /llms.txt could look like:
# Webdimonia
> A premium web design and development studio. Brand identity, custom websites, AI automations, and product design for service businesses. Marketing sites start at $1,500, e-commerce and custom systems at $3,000.
## About
Webdimonia is a studio shipping premium websites and the systems behind them. We build directly with founders, not through account managers. Most marketing sites are 1–4 weeks. The work is owned by the client at the end — code, content, and accounts.
Premium design on the front, real systems behind the scenes: dashboards, payments, notifications, API integrations, and AI automations when the work calls for it. Common use cases: lead routing, inbox triage, review requests, quote drafting.
## Services
- Brand Identity: Logo direction, color systems, and brand assets. Starting at $750.
- Web Design & Development: Custom marketing sites and e-commerce built on Next.js, deployed on Vercel. Marketing sites from $1,500, e-commerce and custom systems from $3,000.
- AI Solutions / Automations: Lead follow-ups, review requests, chatbots, and workflow automation. Custom quoted.
- Product Design: Dashboards, admin panels, portals, and product interfaces. Custom quoted.
## Important pages
- [Homepage](/): Studio overview and current work.
- [Services](/services): Detailed offerings and pricing.
- [Work](/work): Case studies (Reapify, SupplyDivo, Truucore, Lock & Lore).
- [Blog](/blog): Decision-stage and pricing content for buyers researching websites and AI automations.
- [Contact](/contact): Project inquiry form.
## Pricing
Marketing websites start at $1,500. E-commerce and custom website systems start at $3,000. Managed hosting is $79/month. Brand identity starts at $750; AI automations and product design are custom quoted. Final pricing depends on pages, features, backend complexity, automations, and timeline.
## Contact
Email: hey@webdimonia.com
That's roughly the shape. You can include more — locations, team bios, recent project notes — if it adds context an LLM would want.
What to include
- A precise one-line description. What does the site sell, to whom, and what's the price tier.
- Services with one-liners. Helps LLMs categorize your offerings cleanly.
- Links to your most important pages. With brief descriptions of what's on each.
- Pricing transparency. Even a range. LLMs that get asked "how much does this service cost" are looking for an answer they can quote.
- What makes the company specific. Not marketing copy. Just the structural facts.
What to skip
- Marketing fluff. "Our mission is to delight our customers with seamless experiences." LLMs strip this.
- Internal jargon. Acronyms only your team uses.
- Walls of text. This file should be readable in 30 seconds.
- Anything that's not true. Misrepresenting your services to AI crawlers is the same as misrepresenting to humans, with worse compounding consequences.
How to deploy it
It's a static file. On Next.js, the simplest way is a route file that returns plain text:
// src/app/llms.txt/route.ts
export const dynamic = "force-static";
export function GET() {
return new Response(`# Webdimonia\n\n> A studio that...`, {
headers: { "Content-Type": "text/markdown" },
});
}
Or just put it in public/llms.txt. Either works. Most sites we ship now include it.
Should you have one?
If your site is already optimized for AI search citation (good schema, original content, named author, citable claims), adding /llms.txt is a 1-hour cost for a possible upside. We add it to client sites by default.
If your content is thin or generic, fix that first. /llms.txt won't compensate for content that AI crawlers don't think is worth quoting.
Three questions to decide if it's worth your hour
- Is your site doing real AEO work (specific claims, original numbers, schema)? If yes, add
/llms.txt. If not, fix the content first. - Is your business one that LLMs are likely to be asked about? Service businesses, products, comparisons, "best X for Y" — yes. Pure portfolios — less likely.
- Do you already maintain a sitemap.xml? If yes, the muscle memory for keeping
/llms.txtupdated is already there. Add it.
If you want a starter /llms.txt for your site, send us the URL and a sentence on what you offer. We'll send back a draft within a day.