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A2A Agent Interoperability Protocol

Make agents built by different companies on different frameworks and servers talk to each other: Google's Agent2Agent protocol, now hosted by the Linux Foundation, gives agents a common language to discover capabilities, negotiate modalities and collaborate on long-running tasks without exposing internal state or tools

Tool Interface

Interactive tool will be available soon

Features

  • ✓ Built for opaque agents: collaboration rides on published capability descriptions, so neither side hands over its memory, tools or internals
  • ✓ Discovery and negotiation: agents first discover what each other can do, then negotiate whether to interact via text, forms or media
  • ✓ Long-running collaboration: streaming and asynchronous updates suit tasks that run for minutes or hours rather than single question-and-answer turns
  • ✓ Complementary to MCP, not competing: MCP connects agents to tools and data, A2A connects agents to other agents
  • ✓ Neutral governance: Apache 2.0 open source, hosted by the Linux Foundation and then its Agentic AI Foundation, avoiding single-vendor lock-in

How to Use

  1. Separate the two problems first: hand connecting agents to tools and data to MCP, and cross-system agent-to-agent collaboration to A2A
  2. Give each participating agent a capability description and an endpoint, so others can discover it and know what it is good at
  3. Adopt an official SDK: Python, Go, Java, JavaScript, .NET and Rust implementations exist, so you do not invent a protocol dialect
  4. Prove one end-to-end task internally or with a controlled partner — discovery, authentication and streaming updates on a long job — before widening scope

FAQ

What is the A2A protocol?

An open protocol enabling communication and interoperability between opaque agentic applications — that is the official line. Its goal is to let generative AI agents built by different companies on different frameworks and servers collaborate as agents rather than being called as mere tools. See https://a2a-protocol.org/latest/ and https://github.com/a2aproject/A2A

Who governs it now?

Google launched the protocol in April 2025 and donated it to the Linux Foundation on 23 June 2025 at the Open Source Summit North America, giving it neutral governance rather than single-vendor control under Apache 2.0. At its one-year mark in April 2026, an official release reported more than 150 supporting organisations, deep integration across Google, Microsoft and AWS platforms, and production deployments across industries. See https://www.linuxfoundation.org/press/a2a-protocol-surpasses-150-organizations-lands-in-major-cloud-platforms-and-sees-enterprise-production-use-in-first-year

How do A2A and MCP relate? Is it either-or?

Complementary, not either-or. The official framing: MCP connects agents to tools and data, A2A connects agents to other agents. One solves how an agent reaches resources, the other how agents discover, negotiate and collaborate — real multi-agent systems usually run both. See https://a2a-protocol.org/latest/ and https://github.com/a2aproject/A2A

What do agents exchange, and does it leak internals?

Capability descriptions and task messages, not internals. Officially A2A lets agents discover each other's capabilities, negotiate interaction modalities (text, forms, media) and securely collaborate on long-running tasks while operating without exposing their internal state, memory or tools. You learn what a peer can do from its published capability description, not its logs. See https://github.com/a2aproject/A2A

Which languages are supported and how do you start?

The official repository ships implementations and SDKs across Python, Go, Java, JavaScript, .NET and Rust, with quickstarts in the docs. A pragmatic path is to connect two of your own agents internally for one task before reaching out to external partners, which surfaces the fragile spots — discovery, authentication and streaming updates — early. See https://a2a-protocol.org/latest/ and https://github.com/a2aproject/A2A

Is it too early to adopt?

It depends on your situation. If you run a single agent calling a few tools, MCP is enough and A2A is unnecessary; but if you are assembling multi-vendor agents or collaborating with external partners, designing interfaces against an open standard early is cheaper than migrating later. The protocol is Apache 2.0 and foundation-hosted, so governance is comparatively safe. See https://www.linuxfoundation.org/press/a2a-protocol-surpasses-150-organizations-lands-in-major-cloud-platforms-and-sees-enterprise-production-use-in-first-year