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Agent Interop

In Admin → Agent Interop, you register external agent connections and control which protocols are in use. Delegate work to specialist agents inside Fontana, hand off conversations when the task changes, or federate with external platforms over open protocols (A2A, ACP, ANP, OFP). Every delegation runs with allowlisted origins, bearer authentication, and audit metadata.

In-app orchestration patterns

Section titled “In-app orchestration patterns”
SubAgent Delegation

Use SubAgent Delegation to isolate deep work in child threads while the parent keeps context lean.

Agent Handoff

Use Agent Handoff to transfer the root thread to a specialist agent when the task surface changes.

Agent Interop

Use Agent Interop with A2A, ACP, ANP, OFP, and other standards to communicate with external agents.

Pattern Status What it does Configuration
SubAgent delegation Available Spawn a child thread for delegated work, then return results to the parent. Isolates deep work while the parent keeps context lean. subagents on the agent definition in Admin → Agents
Agent handoff Available Transfer the current conversation to another in-app agent on the same thread. Use when the task surface changes. handoffAgents on the agent definition in Admin → Agents

External protocols

Section titled “External protocols”

Configure connections in Admin → Agent Interop. Supported and planned federation protocols:

Protocol Status Technical description Documentation
A2A (Agent2Agent) Available JSON-RPC 2.0 over HTTPS for peer-agent task delegation. Outbound: in-app agents delegate tasks to registered connections with allowlisted origins and bearer auth (env or Vault). Inbound: workspace Agent Card at /.well-known/agent-card.json, per-agent cards, and bearer-authenticated JSON-RPC at /api/a2a/json-rpc. A2A specification
ACP (Agent Communication Protocol) Available REST-native agent messaging with MIME-typed multipart payloads, session identifiers, and manifest-based discovery. ACP specification
ANP (Agent Network Protocol) Coming soon Decentralised peer-to-peer agent networking using W3C Decentralized Identifiers (DIDs) and JSON-LD capability metadata. Complements enterprise A2A when agents must federate across organisational boundaries without a central registry. ANP repository
OFP (Open Floor Protocol) Coming soon Linux Foundation standard for multi-party conversational agents: Conversation Envelopes, Assistant Manifests, and Dialog Events. Supports delegation, mediation, and shared floor control across heterogeneous voice and chat agents. OFP introduction

Inbound and outbound behaviour

Section titled “Inbound and outbound behaviour”
  • Outbound delegation - in-app agents send A2A JSON-RPC tasks to registered peer connections with allowlisted origins and bearer authentication
  • Inbound discovery - workspace publishes an Agent Card at /.well-known/agent-card.json plus per-agent cards
  • Inbound API - bearer-authenticated JSON-RPC at /api/a2a/json-rpc for inbound task execution
  • Admin → Agent Interop - one sidebar for outbound Connections and inbound Agent Cards (workspace Discovery plus per-agent cards); A2A connection CRUD; ACP, ANP, and OFP shown as roadmap placeholders; allowlisted HTTPS origins; audit metadata on tool calls
Section titled “Related documentation”