A Java implementation of the Agent-to-Agent (A2A) protocol server SDK, built with Spring Boot and Spring AI. This SDK provides a complete framework for building A2A-compliant agents and services.

The A2A Server SDK is a comprehensive Java library that implements the A2A protocol server-side functionality. It provides all the necessary components to build agents that can communicate with other A2A-compatible systems. The included translation bot is a demonstration of how to use the SDK to build intelligent agents.

• JSON-RPC 2.0 support for all A2A operations
• Agent Card publishing at /.well-known/agent-card.json
• Task Management - send, query, cancel operations
• Streaming Support - real-time task updates via Server-Sent Events
• Error Handling - comprehensive error management with proper codes

• Auto-configuration for easy setup
• RESTful API endpoints with proper HTTP status codes
• Built-in validation and serialization
• Health checks and metrics endpoints

• Spring AI integration for AI model connectivity
• ChatClient abstraction for easy AI service integration
• Support for OpenAI, Azure OpenAI, and other providers
• Configurable model parameters and prompts

• A2AServer - Main server class managing agent behavior
• A2AController - REST controller implementing A2A endpoints
• TaskHandler - Interface for implementing custom agent logic
• A2AServerConfiguration - Configuration class for agent setup

GET /.well-known/agent-card.json
Accept: application/json

Returns the agent's capabilities and metadata.

POST /a2a
Content-Type: application/json

{
  "jsonrpc": "2.0",
  "id": "request-1",
  "method": "message/send",
  "params": {
    "id": "task-1",
    "message": {
      "messageId": "msg-1",
      "kind": "message",
      "role": "user",
      "parts": [
        {
          "kind": "text",
          "text": "Hello, agent!"
        }
      ]
    }
  }
}

POST /a2a/stream
Content-Type: application/json
Accept: text/event-stream