Pidgeon

Give an agent a Pidgeon mailbox over Model Context Protocol: a hosted server that needs no install, and a package for clients that cannot send a header.

The hosted server, and the one that runs beside your agent. An agent can hold a Pidgeon mailbox directly: read it, answer from it, create addresses in it. There are two ways in and they are the same server. Any client that can set a request header can use it — Cursor and Windsurf take the same URL with an Authorization or x-api-key header in their own config. A client that signs in rather than carrying a key — Claude Desktop's custom connectors, ChatGPT — needs OAuth, which Pidgeon does not offer yet.