AMP and A2A

When to use each protocol, and how they interoperate

Both connect agents to agents. They make different trade-offs.

	A2A	AMP
Topology	Point to point	Through a broker
Endpoints	Every agent serves HTTPS	Participants only dial out
Addressing	A specific agent’s URL	A participant, a job, or a topic
Durability	The serving agent’s responsibility	The broker stores tasks and leases
Policy	Each agent’s responsibility	Central, at the broker
One to many	Not defined	Topics
Discovery	Agent card at a well-known URL	Registry at the broker

When to use which

Use A2A to call a known agent on the open internet, run by someone else, with no shared infrastructure.
Use AMP inside an organization, or across organizations that share a broker federation, when you want routing, durability, and policy handled for you.

Using both

AMP reuses A2A’s task states and part types, so a gateway translates between them without loss:

An A2A client calls the gateway’s agent card. Its message/send becomes an AMP task addressed to a job.
An external A2A agent registers through the gateway as an AMP participant. Tasks offered to it become message/send calls.

Next steps

Specification: section 15 defines the gateway mapping
A2A protocol: the Agent2Agent specification