# llms.txt: how to publish a site summary for AI agents

> /llms.txt published and well-structured: The most widely adopted contract for making a site legible to agents. The fix: publish llms.txt. Standard: llmstxt.org.

- Source: /checks/llms-txt
- Site: AgenticWebScore
- Language: English

---
The most widely adopted contract for making a site legible to agents. In the curated corpus we measured, 46% of sites published one and the average quality score was 37 out of 100 — adoption is not the same as usefulness.

| Property | Value |
| --- | --- |
| Check id | `llms-txt` |
| Dimension | Discoverability (20%) |
| Tier | Essential — pool 80 pts |
| Weight inside tier | 3 |
| Impact | Critical |
| Maturity | Draft — A published specification that is not yet ratified. |
| Conditional | No |
| Publishing skill | `llms-txt` |
| Standards | llmstxt.org |

## What the scanner requests

- `/llms.txt`

## What is measured

The scanner fetches https://<domain>/llms.txt (the exact path this check probes) and parses the markdown against the llmstxt.org contract. It then requests up to 6 same-origin links the file names, beyond the paths the scan already requests. A link on another origin is not requested, and a link that gets no answer is not measured. Pass = a 2xx response served as text/plain or text/markdown, opening with an H1, followed by a blockquote summary and at least one H2 section listing markdown links written as [name](url). No requested same-origin link may answer a status other than 2xx, and the pass states how many links were requested. Partial = the file is served with another content type, has no H1, has an H1 after other lines, has no H2 link list, has no blockquote, or names a requested same-origin link that answered a status other than 2xx. Fail = a non-2xx status for the file, or an HTML document returned for the path. A request for the file that gets no answer is not measured.

## Reproduce it yourself

You do not have to take our word for any of this. Run the same measurement against your own domain:

```bash
DOMAIN=example.com
curl -sS "https://$DOMAIN/llms.txt" | head -25
```

## The fix

This is the artifact to ship. It is the complete change, not a description of one.

```markdown
# Example Inc

> Example Inc runs a payments API for marketplaces. This file lists the pages an agent needs, with a short note on each.

Example Inc is US-based; support is at support@example.com.
API access uses OAuth 2.0 tokens, see the authentication guide below.

## Docs

- [Quickstart](https://example.com/docs/quickstart.md): Install the CLI and make a first API call
- [API reference](https://example.com/docs/api.md): Every endpoint, with request and response examples
- [Authentication](https://example.com/docs/auth.md): OAuth 2.0 flows and token lifetimes

## Company

- [Pricing](https://example.com/pricing.md): Plans, limits and overage rates
- [Status](https://example.com/status): Live service status and incident history

## Optional

- [Changelog](https://example.com/changelog.md): Release notes since 2024
```

> The links should point at markdown versions of the pages, and the file must be served raw - an SPA catch-all that returns index.html for this path scores as a fail.

## Standards referenced

- `llmstxt.org`

## Related checks

| Check | Tier | Impact | Same skill |
| --- | --- | --- | --- |
| `reachable` — Homepage open to agent access | Essential | Critical | — |
| `robots-txt` — robots.txt with agent directives | Essential | High | — |
| `sitemap-xml` — sitemap.xml valid and current | Essential | High | — |
| `link-headers` — Discovery via Link response headers | Emerging | Medium | — |
| `dns-aid` — DNS-AID discovery record | Emerging | Medium | — |
| `canonical` — Canonical and hreflang discipline | Recommended | Medium | — |
| `llms-full` — /llms-full.txt expanded context | Recommended | Low | — |
| `agents-md` — AGENTS.md with the required sections | Recommended | High | — |