A2A + Claude Code: Complete MCP Integration

A2A is a MCP server that An MCP server that bridges the Model Context Protocol (MCP) with the Agent-to-Agent (A2A) protocol, enabling MCP-compatible AI assistants (like Claude) to seamlessly interact with A2A agents..

When integrated with Claude Code, you can:

• Register and manage A2A agents for communication
• Send messages to A2A agents and handle responses
• Manage asynchronous tasks and retrieve results

This guide provides step-by-step instructions to set up A2A in Claude Code, including configuration, examples, and troubleshooting.

What You'll Achieve

After completing this setup:

• A2A will be fully integrated and operational
• You can use A2A tools directly in Claude Code
• All A2A capabilities will be available for your workflows
• Access to 4 different tools

Prerequisites

Before starting, ensure you have:

• Claude Code installed and configured
• Compatible operating system (Windows, macOS, Linux)

Installation

Step 1: Install A2A

Configuration

Step 2: Configure Claude Code

1. Install Claude Code

Download and install Claude Code from the official website

Visit: https://claude.ai/code

Note: Claude Code is available as a native application, not via npm

2. Navigate to Project

Open terminal in your project directory where you want to use the MCP server

3. Install MCP Server

Install the MCP server you want to use (e.g., via npm, pip, or other package manager)

4. Configure MCP Server

Add MCP server configuration to project CLAUDE.md file or use --mcp-config flag

Note: CLAUDE.md is preferred for project-specific configuration

5. Test Integration

Start Claude Code and verify MCP server is working

claude

Note: Use interactive mode to test MCP server functionality

Configuration Details

Add to your project's CLAUDE.md file:

## MCP Servers

### A2A
- **Installation**: a2a
- **Configuration**: "MCP_TRANSPORT": "streamable-http",
        "MCP_HOST": "0.0.0.0",
        "MCP_PORT": "8080",
        "MCP_PATH": "/api/mcp",
        "MCP_DEBUG": "true"
- **Description**: An MCP server that bridges the Model Context Protocol (MCP) with the Agent-to-Agent (A2A) protocol, enabling MCP-compatible AI assistants (like Claude) to seamlessly interact with A2A agents.

Claude Code will automatically detect and load MCP servers from your project context.

Examples

Once configured, you can use A2A in Claude Code:

Register and Communicate with Agent

Set up communication with an A2A agent

Ask Claude Code: "Register an agent for data analysis tasks and send it a dataset processing request"

Expected Result: Agent registered, task submitted, and task_id returned for tracking

Stream Real-Time Data

Use streaming to get real-time updates from agent

Ask Claude Code: "Stream live updates from the monitoring agent about system metrics"

Expected Result: Continuous stream of system metrics and status updates

Manage Multiple Agents

Coordinate tasks across multiple A2A agents

Ask Claude Code: "List all available agents and distribute parallel processing tasks"

Expected Result: Agent list displayed, tasks distributed, and progress tracked

Handle Task Results

Retrieve and process completed task results

Ask Claude Code: "Get the results from the data analysis task I submitted earlier"

Expected Result: Task results retrieved with processed data and analysis findings

Testing Your Setup

1. Run claude in your project directory
2. Ask Claude to list available tools and verify A2A tools are present
3. Test A2A functionality by asking Claude to use specific tools

Test commands:

claude

claude --debug

Troubleshooting

Common Issues

Agent Registration Failed

Symptoms: Registration errors, Agent not found, Connection timeouts

Cause: Network connectivity issues or invalid agent configuration

Solution:

• Check internet connectivity to A2A network
• Verify agent endpoint URLs are correct
• Ensure agent is online and accepting connections
• Check firewall settings and port accessibility

Task Never Completes

Symptoms: Task stuck in pending state, No response from agent

Cause: Agent overload, network issues, or task complexity

Solution:

• Check agent status and availability
• Cancel and resubmit the task
• Break complex tasks into smaller parts
• Try different agent if available

Transport Protocol Errors

Symptoms: Connection refused, Protocol mismatch errors

Cause: Incorrect transport configuration or port conflicts

Solution:

• Verify MCP_TRANSPORT setting matches client expectations
• Check MCP_HOST and MCP_PORT are accessible
• Ensure no port conflicts with other services
• Try different transport mode (stdio, http, sse)

Message Streaming Issues

Symptoms: Broken streams, Incomplete messages, Timeout errors

Cause: Network instability or buffer overflow

Solution:

• Check network stability and bandwidth
• Reduce message frequency or size
• Enable debug logging to trace issues
• Use appropriate buffer sizes for streaming

Server Not Found

Symptoms: Command not found errors, Server tools unavailable

Cause: Server not installed or not in PATH

Solution:

• Verify server installation
• Check PATH environment variable
• Install server globally or in project

Configuration Not Loaded

Symptoms: CLAUDE.md changes not recognized, Old server config used

Cause: CLAUDE.md file not in correct location or format

Solution:

• Ensure CLAUDE.md is in project root
• Verify markdown syntax is correct
• Restart Claude Code session

A2A not appearing in Claude Code

Symptoms: Server not listed, Tools not available

Cause: Configuration or installation issue

Solution:

• Verify configuration syntax
• Check A2A installation
• Restart Claude Code
• Check logs for error messages

Next Steps

Now that A2A is integrated with Claude Code:

• Explore all A2A capabilities through Claude Code
• Check out other MCP servers that work with Claude Code
• Join the MCP community for tips and support
• Consider contributing to A2A development

Need Help?

• Search for A2A documentation
• Check the Claude Code MCP guide
• Join the MCP community discussions