ADTP — production Go implementation using UCAN for agent-to-agent delegation

[Zahanturel]

Hi Brooklyn — I built ADTP, a Go daemon that uses UCAN delegation chains for AI agent identity and authorization across MCP/A2A.

One design choice I'd appreciate feedback on: ADTP adds a RESTRICT mode on top of standard UCAN attenuation. It's a structural invariant — a delegated credential can only narrow its parent's capabilities, enforced at chain validation, not policy evaluation. I tested it against 7 adversarial escalation vectors (scope widening, depth bypass, RESTRICT removal, caveat stripping, cross-org escalation, replay injection, malformed caveats). Zero bypasses.

The other piece: cascade revocation with a registration invariant that guarantees every descendant is dead the moment an ancestor is revoked. No background jobs, no eventual consistency.

12.6k lines of Go, Apache 2.0, 22-finding security audit resolved: github.com/Zahanturel/adtp

Would value your take on the UCAN usage patterns — especially whether RESTRICT mode is something worth proposing as a spec extension.