A2A Protocol

Agent2Agent
Protocol

A new era of agent interoperability. Enable seamless collaboration between AI agents across different platforms and frameworks.

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A2A

What is A2A Protocol?

A2A Protocol is an open standard that enables AI agents to communicate and collaborate across different platforms and frameworks, regardless of their underlying technologies. It's designed to maximize the benefits of agentic AI by enabling true multi-agent scenarios.

Universal Interoperability

Enables agents to work together seamlessly across different platforms and frameworks, regardless of their underlying technologies.

Enterprise-Grade Security

Built with enterprise-grade authentication and authorization, supporting OpenAPI's authentication schemes.

Flexible & Scalable

Supports everything from quick tasks to long-running research, with real-time feedback and state updates.

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Key Features

A2A Protocol is designed with five key principles to enable effective agent collaboration

Open Standard

Built on existing standards including HTTP, SSE, and JSON-RPC for easy integration with existing IT stacks

Secure by Default

Enterprise-grade authentication and authorization with support for OpenAPI's authentication schemes

Multi-Modal Support

Supports various modalities including text, audio, and video streaming for comprehensive agent communication

Long-Running Tasks

Designed to support both quick tasks and deep research that may take hours or days to complete

Agent Collaboration

Enables true multi-agent scenarios where agents can collaborate in their natural, unstructured modalities

Real-Time Updates

Provides real-time feedback, notifications, and state updates throughout the task lifecycle

How A2A Works

A2A facilitates communication between a 'client' agent and a 'remote' agent through a structured process

How A2A Works
01

Capability Discovery

Agents advertise their capabilities using an 'Agent Card' in JSON format, enabling other agents to identify the best agent for a task.

02

Task Management

Communication is oriented towards task completion, with a defined lifecycle that can be completed immediately or over time.

03

Collaboration

Agents can send messages to communicate context, replies, artifacts, or user instructions.

04

User Experience

Messages include 'parts' with specified content types, allowing agents to negotiate the correct format and UI capabilities.

Typical Flow

The A2A Protocol follows a well-defined flow for agent communication and task processing.

A2A Protocol Flow

Discovery

Client fetches the Agent Card from the server's well-known URL.

Initiation

Client sends initial message with a unique Task ID.

Completion

Task reaches terminal state (completed/failed/canceled).

A2A ❤️ MCP

TLDR; Agentic applications needs both A2A and MCP. We recommend MCP for tools and A2A for agents.

A2A and MCP

Why Protocols?

  • Standard protocols are essential for enabling agentic interoperability, particularly in connecting agents to external systems.
  • Tools are primitives with structured inputs and outputs and (typically) well-known behavior.
  • Agents are autonomous applications that can accomplish novel tasks by using tools, reasoning, and user interactions.

Complementary

  • MCP is the emerging standard for connecting LLMs with data, resources, and tools.
  • A2A is an application level protocol that enables agents to collaborate in their natural modalities.

Example

  • Consider an auto repair shop that fixes cars.
  • MCP connects agents with their structured tools.
  • A2A enables ongoing communication and collaboration.

Unlock the Future of Agent Interoperability

Join leading technology companies in standardizing agent communication and collaboration

Built for Developers

Join over 50 technology partners including Atlassian, Box, Cohere, Intuit, Langchain, MongoDB, PayPal, Salesforce, SAP, ServiceNow, UKG, and Workday

Specification

Review the full A2A protocol specification and understand how to implement it in your systems.

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Code Samples

Explore available code samples to understand the protocol's structure and experiment with its implementation.

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Documentation

Access comprehensive guides, tutorials, and API documentation to get started with A2A Protocol.

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Join the A2A Community

Be part of the movement to standardize agent interoperability and unlock the full potential of AI agents

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