Directory
The services AI assistants can actually use.
164 services that an AI assistant can call directly — through an MCP server, an app inside ChatGPT or Claude, a published API or an llms.txt — each checked against the service's own public files.
The landscape in numbers
What was found when this directory was compiled, 2026-10-04.
- Servers in the MCP Registry
- 37,928
- Sites checked
- 1,504
- With a real llms.txt
- 952
- With an MCP manifest
- 242
MCP Registry servers by category
| other | 10,766 | |
|---|---|---|
| developer | 8,596 | |
| data | 5,447 | |
| finance | 4,277 | |
| productivity | 3,568 | |
| media | 2,234 | |
| maps & transport | 784 | |
| health | 654 | |
| travel | 503 | |
| shopping | 492 | |
| real estate | 315 | |
| food & delivery | 292 |
Categories assigned by keyword from each server's own summary; deprecated, empty and test entries excluded.
What the sites answered
| File | HTTP 200 | Real file |
|---|---|---|
/llms.txt | 1,015 | 952 |
/.well-known/mcp.json | 335 | 242 |
/.well-known/ai-plugin.json | 176 | 75 |
/agents.json | 147 | 24 |
Of 1,504 sites. A 200 that returned an HTML page or an error document is not counted as a real file.
By access type
MCP server
A Model Context Protocol server: a standard interface that AI assistants such as Claude, ChatGPT and others can connect to, to call the service's tools directly.
ChatGPT app
An app inside ChatGPT: the assistant can call the service while you chat, after you connect it.
Claude connector
A connector in Claude: the assistant can read from or act in the service once you connect it.
OpenAPI description
A published machine-readable API description that an agent can read to learn how to call the service.
llms.txt
A plain-text guide at /llms.txt that tells AI systems what the site is and where its key pages are.
Public API
A documented public API an agent can call, usually with a key from the service.
Categories
Learn
What is an MCP server?
The Model Context Protocol (MCP) is an open standard for connecting AI assistants to outside tools and data. A service that runs an MCP serv…
What is llms.txt?
llms.txt is a plain-text file at the root of a website — /llms.txt — that tells AI systems what the site is and lists its most useful pages …
How AI assistants find and book travel
An assistant answering a travel question has three ways to get facts: from what it learned in training (often out of date), from searching t…
How listings are verified
For every service, the directory requests the public files that declare an AI integration — /llms.txt, MCP manifests, OpenAPI descriptions —…