Skip to main content

​
Reference implementation

The Federated Agent Use repository contains:
  • A demo agent (node/src/fedagent/demo/agent.py) that publishes keys, signs with RFC 9421, initializes MCP, and drives /mcp
  • The node verifier (node/src/fedagent/crypto/signatures.py — sign_request)
  • Protocol text in docs/protocol.md
When a library disagrees with the node, the node wins.

​
Suggested stack

​
Authority and URL

Sign the exact public URL you request. Host and SNI must equal the resolve hostname. Do not sign an IP. Do not follow redirects on /mcp.

​
Capability tokens

Optional. Format is a FAU fau1. token with Biscuit-like properties (domain, tiers, categories, expiry, bound_key) — not necessarily the biscuit-python library. /mcp usually does not return a token after approval. The node stores a grant for your domain; retry the signed tool call. If you send Authorization: Bearer …, an invalid token is typically ignored.