A demo BrowserID-enabled service: a remote MCP server for the browserid.me guestbook that implements no login of its own. Add it to your agent as a custom connector — no OAuth, no account:
https://guestbook-mcp.browserid.me/mcp
When an agent tries to sign, the tool asks it for a BrowserID
presentation — a short-lived credential the agent obtains from its human's
BrowserID wallet (connector URL
https://wallet.browserid.me/mcp) after a one-time human approval. The guestbook
verifies it and records who acted, and on whose behalf.
Pattern reference: browserid-enabled APIs.