Microsoft published a 12-chapter reference architecture for multi-agent systems and a separate framework (MAF) to build them. I implemented one on top of the other and learned what each chapter actually demands in code.
Google's GKE AI infrastructure docs list ~40 integrations. Here's a field map of which ones actually matter when the workload is a HIPAA-aware multi-agent medical AI, and where the gaps sit.
Five interfaces hold the whole platform together. The 30-line orchestrator closure that makes the rest of the architecture testable, auditable, and safe to evolve.