%% You should probably cite draft-mpsb-agntcy-messaging-03 instead of this revision. @techreport{mpsb-agntcy-messaging-00, number = {draft-mpsb-agntcy-messaging-00}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-mpsb-agntcy-messaging/00/}, author = {Luca Muscariello and Michele Papalini and Mauro Sardara and Sam Betts}, title = {{An Overview of Messaging Systems and Their Applicability to Agentic AI}}, pagetotal = 19, year = , month = , day = , abstract = {Agentic AI systems require messaging infrastructure that supports real-time collaboration, high-volume streaming, and dynamic group coordination across distributed networks. Traditional protocols like AMQP, MQTT, and NATS address some requirements but fall short on security, particularly regarding {[}AMQP{]} {[}MQTT{]} {[}NATS{]} post-compromise protection and quantum-safe encryption essential for autonomous agents handling sensitive data. This document analyzes six messaging protocols—AMQP, MQTT, NATS, AMQP over WebSockets, Kafka, and AGNTCY SLIM—across dimensions critical for GenAI agent systems: streaming performance, delivery guarantees, security models, and operational complexity. We examine how each protocol's design decisions impact agentic AI deployments, from lightweight edge computing scenarios to large-scale multi- organizational collaborations. AGNTCY SLIM emerges as a purpose-built solution, integrating Message Layer Security (MLS) {[}RFC9420{]} with gRPC {[}gRPC{]} over HTTP/2 {[}RFC7540{]} to provide quantum-safe end-to-end encryption, efficient streaming, and OAuth-based authentication {[}RFC6749{]}. Unlike transport-layer security approaches, SLIM's MLS implementation ensures secure communication even through untrusted intermediaries while supporting dynamic group membership changes essential for collaborative AI agents.}, }