# WellKnownMCP

Home > Browse > By type > documentation > wellknownmcp.org

> Probe-verified (tier 2 of 3). Last checked 2026-08-23. 2 of 5 capability checks passed.

- host: wellknownmcp.org
- url: https://wellknownmcp.org/
- category: agent-native domain tools
- type: documentation
- language: en

## Probe-verified · tier 2 of 3

Probed live on 2026-08-23 against rubric v1. 2 of 5 checks passed.

- PASS — Markdown negotiation
- fail — Markdown twin at a predictable URL
- PASS — llms.txt
- fail — API catalog
- fail — MCP server answers

## Unverified actions

Read from the page's own content, with the wording each was drawn from. Inference is kept separate from tested facts; an agent completing the action is tier 3.

- **read** — "occasional, signed write-ups when something in the agentic-web space actually changes" → `https://wellknownmcp.org/en/news`
- **read** — "live probes for any domain: MCP handshake, OAuth discovery chain, llms.txt, security.txt" → `https://wellknownmcp.org/check`
- **read** — "how fast the MCP registry is growing, counted weekly from the official registry API" → `https://wellknownmcp.org/radar`
- **read** — "evergreen, practical notes: llms.txt done right, AGENTS.md that’s agent-verifiable" → `https://wellknownmcp.org/guides`

## Summary

Provides doctrine, tools, and reference implementations for agent-native domain discoverability and MCP federation.

## Context

4824 sites in this index share the type "documentation"; 1246 are transactional.

## How we grade

- tier 1 — **Declared**: The site says agents are welcome in its robots.txt. A permission, not a capability.
- tier 2 — **Probe-verified** (this site): We fetched the site and tested each signal ourselves. Dated, repeatable, re-checked on a schedule.
- tier 3 — **Behaviourally verified**: An agent completed the action end to end — booked, bought, submitted — and it worked.

## About this record

Known-Good probes sites live and publishes what was tested and when.
Method: https://knowngood.sh/about.md · Rubric: https://knowngood.sh/benchmark

## Where this sits

- documentation: https://knowngood.sh/type/documentation
- agent-native domain tools: https://knowngood.sh/category/agent-native-domain-tools
- Browse: https://knowngood.sh/browse
- Rubric: https://knowngood.sh/benchmark