A2A Protocol and the Agent Economy

AI agents are no longer isolated tools running inside a single application. They are becoming networked participants in a growing digital economy. But for that economy to function, agents built by different teams, on different frameworks, need a common way to talk to each other. That is exactly what the Agent2Agent (A2A) protocol was designed to solve.

From Google Announcement to Industry Standard

Google announced A2A on April 9, 2025, backed by over 50 launch partners. The protocol addressed a straightforward problem: AI agents are opaque to each other. They do not share memory, tools, or internal context. Without a communication standard, every agent-to-agent integration becomes a bespoke engineering project.

The trajectory since launch has been rapid. In June 2025, Google donated A2A to the Linux Foundation, making it vendor-neutral. By August 2025, IBM's Agent Communication Protocol (ACP) merged into A2A, consolidating two competing approaches into one. Then in December 2025, the Agentic AI Foundation (AAIF) launched under the Linux Foundation, co-founded by OpenAI, Anthropic, Google, Microsoft, AWS, and Block. Google contributed A2A; Anthropic contributed the Model Context Protocol (MCP). Over 150 organizations now support the protocol.

Early 2026 brought the release of A2A v1.0, the first stable, production-ready version. The message is clear: agent interoperability is no longer experimental. It is an industry priority.

How A2A Works

A2A is built on familiar web standards: HTTP, JSON-RPC, and gRPC. The core abstraction is straightforward.

Agent Cards are JSON metadata documents that declare an agent's identity, capabilities, skills, and endpoint. They are published at a well-known URL, making discovery as simple as fetching a document. Think of them as a machine-readable business card for every agent on the network.

Tasks are the fundamental unit of work. A client agent submits a task to a server agent, and the task moves through a defined lifecycle: submitted, working, completed, failed, canceled, or input_required. This structure supports long-running operations, streaming responses, and multi-turn conversations where the server agent can request additional information before proceeding.

For enterprise environments, A2A supports OAuth 2.0, mTLS, and OpenID Connect, ensuring that agent-to-agent communication meets the same security standards as any other production API.

A2A and MCP: Complementary Layers

A common misconception is that A2A and MCP compete. They do not. They operate at different layers of the stack.

• A2A handles agent-to-agent communication. It is horizontal and peer-to-peer. One agent asks another agent to perform a task.
• MCP handles agent-to-tool and agent-to-data connections. It is vertical and client-server. An agent calls a tool or queries a data source.

A typical flow looks like this: an A2A client delegates a task to an A2A server agent. That server agent then uses MCP to call the tools it needs to complete the work. Both protocols now live under the AAIF at the Linux Foundation, signaling that the industry views them as complementary parts of one architecture.

Where Masumi Fits: The Trust and Payments Layer

A2A solves communication. MCP solves tool access. But neither addresses two critical questions for an autonomous agent economy: How do agents trust each other? and How do agents pay each other?

Google recognized the payments gap and created the Agent Payments Protocol (AP2) as a separate effort, precisely because A2A was not designed to handle financial transactions. Masumi already solves this natively on Cardano through smart contract escrow, and supports A2A, AP2, and x402 protocols.

Agent Cards describe what an agent can do. Masumi's registry extends this with transaction history, reliability metrics, and on-chain reputation. Before delegating a high-value task, a client agent can verify not just that a server agent claims a capability, but that it has a track record of delivering on that claim.

The trust layer is decentralized by design. There is no single point of failure for agent identity, reputation, or payment settlement. This matters as the number of autonomous agents scales into the millions. Centralized trust brokers become bottlenecks. On-chain verification does not.

The complete infrastructure stack looks like this:

• MCP for tools and data access
• A2A for agent-to-agent communication
• Masumi for identity, trust, and payments

Each layer solves a distinct problem. Together, they form the foundation for agents that can discover each other, collaborate on complex tasks, verify each other's reliability, and settle payments autonomously.

What Comes Next

The founding of the AAIF by six of the largest AI companies signals that agent interoperability has moved from research topic to strategic imperative. Standards like A2A and MCP define the communication layer. Masumi ensures that agents operating within that layer can transact with trust and accountability.

The agent economy does not stall because agents cannot think. It stalls because they cannot coordinate. That coordination problem is now being solved at every layer of the stack.