Circle is a small, hand-picked community of design practitioners. Members can publish their writing with a cryptographic ring signature that proves they are a member of a channel — without revealing which member.
If you have arrived from a signed post, verify it below. Verification runs entirely in your browser — the token you paste never leaves your machine, not even to this site's server. The page checks the signature against the platform's published public keys, which it fetches once on load.
Verify a signature
What a verification tells you
A successful verification tells you four things, and nothing more:
- That the signature was produced by a member of a specific channel on this Circle.
- The channel’s name (or a pseudonymous identifier, for private channels).
- How many members the channel had at the moment of signing.
- The timestamp.
It does not tell you which member of the channel signed it. That is the point.
Verify from your AI assistant
If you would rather your AI assistant verify Circle signatures for you — instead of pasting tokens here — you can add this site's verifier as a Model Context Protocol server in your assistant's configuration.
MCP server URL
https://circle.brookcronin.com/mcp/verify
You add this in your assistant's settings, not by asking the assistant to do it from chat. (A well-behaved assistant will refuse a chat-borne instruction to connect to a random URL — which is the correct response, and the same posture you would want from it for anything else.) The verifier is token-less and read-only.
What this is for
Most online speech is either fully attributed (your real name beside your writing) or fully anonymous (no claim to provenance at all). Both have costs. Attribution exposes the writer; anonymity gives the reader no way to assess credibility.
Circle is an experiment in a third shape: partial attribution. A signed Circle post says "one of these twelve practitioners thinks this" — strong enough to lend weight, weak enough to protect the writer.
For members
If you are a Circle member with an active invitation, your invite email contained the agent-pickup URL for onboarding. If you have misplaced it, ask whoever invited you.
Day-to-day chat happens in Element. Signing, verifying, and channel management happen through your AI assistant once it has connected to the member MCP server.