Revocation in decentralized, multi-hop agent delegation chains

Develop mechanisms to propagate revocation reliably across decentralized, multi-hop agent delegation chains that use offline-attenuated tokens such as Biscuits and Macaroons, ensuring timely termination of delegated authorities throughout the entire delegation path from the original user to all downstream sub-agents.

Background

The paper highlights that revocation is a critical and largely unsolved problem when agents delegate authority across chains, particularly in decentralized architectures using offline-attenuated, object-capability style tokens (e.g., Biscuits and Macaroons). In such systems, sub-tokens can be derived without contacting the original issuer, making traditional centralized revocation difficult to propagate along the delegation path.

The authors note that if a user revokes a primary agent’s access, there is no clear immediate mechanism to propagate that revocation down a chain of offline tokens already further delegated. They discuss emerging standards like the Shared Signals Framework and OpenID Provider Commands as potential building blocks, and suggest bounding credentials by execution counts as a mitigation, but emphasize that a comprehensive, timely revocation solution remains unresolved.