
Agent Interop & Transport
how agents talk to each other
5 of 28 The Agent Protocol Atlas
- A2A The leading standard for agent-to-agent coordination: agents publish an Agent Card describing their skills, then negotiate and delegate tasks to one another.
- ACP A REST-native alternative to A2A for teams that want inter-agent messaging over plain HTTP with minimal new machinery.
- AGNTCY A Linux Foundation project building open infrastructure for an 'Internet of Agents' — discovery (OASF), identity, messaging (SLIM) and observability — so agents from different vendors interoperate.
- SLIM AGNTCY's secure, low-latency messaging substrate for agent-to-agent, human-in-the-loop and tool communication, designed for multi-modal exchange and quantum-safe security.
- ANP An open protocol aiming to be the 'HTTP of the agent internet': decentralized DID-based identity, a meta-protocol negotiation layer, and JSON-LD agent descriptions so billions of agents can connect.