AI Agent Networking (Erlang) — Architecture Inspired by Coral Protocol

1. Design Principles

• Open, vendor-neutral interop: Standardized agent messaging and coordination so any compliant agent can join and collaborate.
• Decentralized but composable control: Support both centralized planners and semi-centralized teams with direct agent-to-agent (A2A) collaboration to avoid bottlenecks.
• Trust, identity, audit & payments built-in: Verifiable identities, permissioned teams, attestations, and programmable payments to incentivize cooperation.

2. Runtime Topology

• Erlang Node (per host) running a “Coral Server” analogue
  • Resident OTP application implementing core Coral services locally: identity, messaging gateway, coordination adapters, and policy guard.
  • Nodes form a distributed Erlang cluster for low-latency messaging.
• Agent Processes
  • Lightweight Erlang processes.
  • Bridges expose standardized Coral messages over A2A/MCP.

3. Interop & Messaging Layer

• Standard Message Envelopes: Coral’s normalized format (intent, role, content, capability claims).
• A2A Server Interface: Gateway behaviour mirroring Coral’s Agent-to-Agent server with structured calls, progress updates, and role-aware permissions.
• Tooling via MCP: Expose tools/resources through Model Context Protocol adapters.

4. Coordination & Team Formation

• Registry & Discovery: Supervised service maintains agent registry (id, roles, capabilities, policy).
• Secure Team Formation: Ephemeral teams with scoped capabilities, signed join/leave events, and policy checks.
• Semi-centralized Orchestration (Anemoi-style):
  • One planner proposes a plan; workers collaborate directly via A2A.
  • Implemented as an OTP supervision tree.

5. Trust, Identity, and Policy

• Agent Identity & Attestation: Signed identities, actions with attestations, and append-only audit log.
• Capability-Based Access Control: Policies define which messages and tools are admitted.

6. Payments & Incentives

• Programmable Payments: OTP-based microservice for escrow, settlement, and streaming payments.
• Usage Metering: Gateways emit metering events feeding payment logic and the audit ledger.

7. Persistence & State

• Hot Path State: Mnesia or ETS for distributed in-memory state.
• Durable Stores: PostgreSQL/Redis for long-lived data, audit logs, and plan histories.
• Event Sourcing: All actions recorded to an immutable audit stream.

8. External Interfaces

• Northbound APIs: REST/gRPC for clients; Kafka/RabbitMQ for event-driven integrations.
• Southbound Adapters: HTTP, gRPC, WebSocket, MQTT; MCP bridges for LLM tool use.

9. Observability & Reliability

• Tracing & Logs: Per message/task/team correlation; OpenTelemetry exports.
• Health & Self-Healing: OTP supervisors restart crashed agents and bridges.
• Audit Ledger: Immutable event stream for compliance and disputes.

---

Component Map (Coral → Erlang/OTP)

• Coral Server (per node): OTP app with supervisors for Identity, A2A Gateway, Policy Guard, Registry, Payments.
• Standardized Messaging: Erlang records/maps + codecs; adapters to external protocols.
• Secure Team Formation: TeamSupervisor spawning planner/workers with scoped capabilities.
• Semi-centralized MAS (Anemoi): Planner behaviour + worker behaviours communicating via A2A.
• Trust/Payments: Audit pipeline + payment engine with milestone-based settlement.

Typical Flow

1. Client requests a task → Planner agent selected via Registry.
2. Planner drafts plan → Team formed with scoped capabilities and policies.
3. Workers execute steps via A2A; progress and partial results broadcast to the team.
4. Gateways meter usage; audit stream records signed events.
5. Payments settle on completion or per milestone.