---
title: ".well-known defined | Agent Ready Checklist"
description: ".well-known: URI prefix defined in RFC 8615 for site-wide metadata at fixed paths. Agents reached one in about 23% of traced runs."
canonical: https://agentreadychecklist.com/glossary/well-known
site: "Agent Ready Checklist"
last_updated: 2026-11-05
section: "Glossary"
---

# .well-known defined | Agent Ready Checklist

> .well-known: URI prefix defined in RFC 8615 for site-wide metadata at fixed paths. Agents reached one in about 23% of traced runs.

Source: https://agentreadychecklist.com/glossary/well-known
Site: Agent Ready Checklist
Last reviewed: 2026-11-05
Agent endpoints: https://agentreadychecklist.com/llms.txt (index), https://agentreadychecklist.com/openapi.json (API), https://agentreadychecklist.com/mcp (MCP server), https://agentreadychecklist.com/ask (search)
Access: https://agentreadychecklist.com/auth.md (no key). Pricing: https://agentreadychecklist.com/pricing.md (free).

# .well-known

URI prefix defined in RFC 8615 for site-wide metadata at fixed paths. Agents reached one in about 23% of traced runs. Example: /.well-known/oauth-authorization-server. Related rows: AR-FIND-04, AR-READ-06, AR-ACT-01, AR-ACT-04, AR-ACT-10, CF-OAUTH-DISCOVERY. Cloudflare isitagentready checks the ARD manifest at /.well-known/ai-catalog.json and wants Content-Type application/json, HTTP 200 and Access-Control-Allow-Origin: \*. The guide "One-day agent-readiness sprint" covers a row that names .well-known.

## Definition

URI prefix defined in RFC 8615 for site-wide metadata at fixed paths. Agents reached one in about 23% of traced runs.

## Example

```text
/.well-known/oauth-authorization-server
```

## Where it appears on the checklist

-   [AR-FIND-04](https://agentreadychecklist.com/checklist/ar-find-04/)AI Catalog at .well-known: Publish an AI Catalog at /.well-known/ai-catalog.json listing every agent-facing resource (MCP server card, OpenAPI, A2A card, docs, llms.txt, skills), linked with <link rel="ai-catalog"> and an HTTP Link header.
-   [AR-READ-06](https://agentreadychecklist.com/checklist/ar-read-06/)Link the discovery files: Link discovery files (llms.txt, .well-known/\*, openapi.json) from content agents already visit: the footer, <link rel="alternate"> in the head, or a resources section.
-   [AR-ACT-01](https://agentreadychecklist.com/checklist/ar-act-01/)Auth an agent can finish: Make authentication completable by an agent: self-serve keys with documented scopes; for user-delegated access, OAuth 2.0 with metadata under /.well-known.
-   [AR-ACT-04](https://agentreadychecklist.com/checklist/ar-act-04/)MCP server card: Ship an MCP server card for pre-connection discovery.
-   [AR-ACT-10](https://agentreadychecklist.com/checklist/ar-act-10/)An MCP server or a CLI: A product agents are expected to act on exposes at least one interface an agent can act through: an MCP server (AR-ACT-03) or a CLI (AR-ACT-06).
-   [CF-OAUTH-DISCOVERY](https://agentreadychecklist.com/checklist/cf-oauth-discovery/)OAuth discovery files: Serve OAuth or OIDC discovery JSON at /.well-known/oauth-authorization-server or /.well-known/openid-configuration with issuer, authorization\_endpoint, token\_endpoint and jwks\_uri; serve RFC 9728 metadata at /.well-known/oauth-protected-resource.
-   [Guide](https://agentreadychecklist.com/guides/one-day-agent-readiness-sprint/)The one-day agent-readiness sprint
-   [Guide](https://agentreadychecklist.com/guides/ship-llms-txt-and-link-it/)How to ship llms.txt and link it
-   [Guide](https://agentreadychecklist.com/guides/publish-openapi-agents-can-find/)How to publish an OpenAPI file agents can find

## Asked about it

### How do I make an OpenAPI file agents find?

Serve the raw file, link it from docs and the home page, and list it in /.well-known/api-catalog with a service-desc link. On sites that shipped one, 97% of openapi.json fetches came through a link.

### What OAuth files should an agent be able to find?

Authorization server metadata at /.well-known/oauth-authorization-server (RFC 8414) or OIDC discovery, and protected resource metadata at /.well-known/oauth-protected-resource (RFC 9728). Cloudflare checks both separately.

## Sources

-   [rfc-editor.org/rfc/rfc8615](https://www.rfc-editor.org/rfc/rfc8615)read 2026-11-04
-   [isitagentready.com/.well-known/agent-skills/ard/SKILL.md](https://isitagentready.com/.well-known/agent-skills/ard/SKILL.md)read 2026-11-04
-   [github.com/agentready-org/standard/blob/main/spec/spec.md](https://github.com/agentready-org/standard/blob/main/spec/spec.md)read 2026-11-04
-   [isitagentready.com/.well-known/agent-skills/oauth-discovery/SKILL.md](https://isitagentready.com/.well-known/agent-skills/oauth-discovery/SKILL.md)read 2026-11-04

Last reviewed 2026-11-05. AgentReady v2.0, read 2026-11-04.