Samples using the Agent2Agent (A2A) Protocol
Agent2Agent (A2A) Samples
Welcome to the official code samples and demonstrations for the Agent2Agent (A2A) Protocol.
We are thrilled to have you here! Whether you are exploring multi-agent architectures for the first time or building advanced interoperable agent networks, this repository provides simple, inspiring, and accessible learning resources to accelerate your development.
Why Agent2Agent?
In a world of diverse AI frameworks and ecosystems, agents need a common language to communicate, collaborate, and delegate tasks securely. The A2A protocol establishes a standardized, open standard for multi-agent interoperability.
Our samples demonstrate how easily complex multi-agent problems can be solved across different languages and host applications.
Quick Start
Get up and running immediately by launching a Helloworld agent and communicating with it via our Python CLI host.
Start the Agent Server: Open a terminal and start the Helloworld agent server:
cd samples/python/agents/helloworld uv run .Run the Host Client: Open a second terminal and run the CLI client to send a task to the agent:
cd samples/python/agents/helloworld uv run test_client.py
Repository Structure
The repository is organized into several key directories by language:
| Directory | Description |
|---|---|
| samples | Core A2A samples organized by programming language. |
| samples/python | Demonstrates Python agent implementations using the A2A Python SDK. |
| samples/go | Demonstrates Go agent implementations using the A2A Go SDK. |
| samples/dotnet | Demonstrates C# agent implementations using the A2A .NET SDK. |
| samples/java | Demonstrates Java agent implementations using the A2A Java SDK. |
| samples/js | Demonstrates Node.js agent implementations using the A2A JavaScript SDK. |
Contributing
We welcome and encourage contributions of all skill levels! If you have an idea for a new sample, a bug fix, or a documentation improvement, please check out our Contributing Guide.
Getting Help
We are dedicated to providing a welcoming and supportive community. If you have questions, feedback, or run into any issues, please reach out on our issues page.
Related Repositories
| Repository | Category | Description |
|---|---|---|
| A2A | Core Specification | A2A Specification and documentation. |
| a2a-inspector | Tooling | UI tool for inspecting A2A enabled agents. |
| a2a-tck | Testing | Test suite for validating A2A Protocol compliance. |
| a2a-itk | Testing | Toolkit to verify compatibility across different A2A SDK implementations and versions using multi-hop traversal model and varied transport protocols. |
| a2a-python | SDK (Python) | Official Python SDK for A2A. |
| a2a-go | SDK (Go) | Official Go SDK for A2A. |
| a2a-java | SDK (Java) | Official Java SDK for A2A. |
| a2a-js | SDK (JavaScript) | Official Node.js/JavaScript SDK for A2A. |
| a2a-dotnet | SDK (C#/.NET) | Official C#/.NET SDK for A2A. |
| a2a-rs | SDK (Rust) | Official Rust SDK for A2A. |
Disclaimer
Important: The sample code provided is for demonstration purposes and illustrates the mechanics of the Agent-to-Agent (A2A) protocol. When building production applications, it is critical to treat any agent operating outside of your direct control as a potentially untrusted entity.
All data received from an external agent—including but not limited to its AgentCard, messages, artifacts, and task statuses—should be handled as untrusted input. For example, a malicious agent could provide an AgentCard containing crafted data in its fields (e.g., description, name, skills.description). If this data is used without sanitization to construct prompts for a Large Language Model (LLM), it could expose your application to prompt injection attacks. Failure to properly validate and sanitize this data before use can introduce security vulnerabilities into your application.
Developers are responsible for implementing appropriate security measures, such as input validation and secure handling of credentials to protect their systems and users.