Cloudflare Amazon Cloudflare This document defines the "Signature Agent Card", a JSON metadata document that a signature agent using HTTP Message Signatures for bots publishes to describe itself: its identity, purpose, rate expectations, and cryptographic keys. Its parameters are drawn from the OAuth Dynamic Client Registration Metadata registry, the same namespace used by OAuth Client ID Metadata Documents, extended with a single web_bot_auth object. This document registers that object with IANA and establishes a registry for its members.