Show HN: Agent Passport – signed authorization envelopes for AI agents (github.com)

AI agents need the equivalent of OAuth scopes + JWTs, but for actions and spend — not just identity. Agent Passport is an open protocol + TypeScript SDK that issues Ed25519-signed delegation envelopes: scoped permissions, spend caps, time windows, and cascade revocation. Sub-agents get derived passports that can only narrow scope, never escalate. 10-line setup, works with MCP/LangChain/CrewAI. MIT. Curious what people think of the token format