A2A Client SDK

A Java implementation of the Agent-to-Agent (A2A) protocol client SDK, providing a comprehensive framework for communicating with A2A-compliant agents and services.

Overview

The A2A Client SDK is a pure Java library that implements the client-side functionality for the A2A protocol. It provides all necessary tools to discover, communicate with, and manage tasks with A2A-compatible agents. The included translation client examples demonstrate how to use the SDK to interact with intelligent agents.

Key Features

🌐 Complete A2A Protocol Client

• JSON-RPC 2.0 client implementation for all A2A operations
• Agent Discovery via agent card retrieval
• Task Operations - send, query, cancel with full lifecycle management
• Streaming Support - real-time task updates with event listeners
• Error Handling - comprehensive error management with proper A2A error codes

🔧 Easy Integration

• Pure Java implementation with minimal dependencies
• Thread-safe operations for concurrent usage
• Builder patterns for easy configuration
• Configurable timeouts and retry logic

📡 HTTP Client Features

• Synchronous and asynchronous operations
• Connection pooling for optimal performance
• Custom headers and authentication support
• Configurable SSL/TLS settings

🔄 Streaming Support

• Server-Sent Events (SSE) for real-time updates
• Event listeners for handling streaming responses
• Automatic reconnection with configurable backoff
• Error recovery for network interruptions

Architecture

Key Classes

• A2AClient - Main client class for A2A operations
• JSONRPCRequest - Request building and serialization
• JSONRPCResponse - Response parsing and validation
• StreamingEventListener - Interface for streaming event handling
• A2AClientException - A2A-specific error handling