Probing the MCP registry for anonymous access

Thu, 27 Aug 2026 12:00:00 +0200

The Model Context Protocol, or MCP for short, is “an open-source standard for connecting AI applications to external systems”.

In this post, I briefly try to understand how open such an ecosystem is. I’ll use a very simple definition: as a client, does a server require me to log in, does it have a login facility, or is it completely open?

The result is that authentication is common in the part of the MCP ecosystem I measured. About 28% of remote endpoints required it to list tools, while another 23% advertised it. I do not have a good comparison with the Web, even though this seems quite high.

Open Web on Thibault Meunier

Probing the MCP registry for anonymous access