mcp server

Handler

A2A protocol client for your terminal

alDuncanson/Handlercommunitylistedunreviewednot running here yet

Use tool

Set up

Runs on your computer. Pick your agent and operating system.

Before you start

uv (`curl -LsSf https://astral.sh/uv/install.sh | sh`)

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "handler": {
      "command": "uvx",
      "args": [
        "a2a-handler"
      ]
    }
  }
}

same format Cursor, GitHub Copilot CLI, Junie, JetBrains AI Assistant, Augment (Auggie CLI), Factory Droid, Kiro, Devin CLI +12

Values in angle brackets are placeholders. Restart Claude Desktop after editing its config.Claude Desktop docs

README

synced Oct 15, 2026

Handler

Handler is an open-source A2A protocol client for software engineers building, testing, and operating agentic systems. It provides an interactive TUI, a scriptable CLI with structured output, and an MCP server that lets other agents integrate with A2A services directly. Handler also supports global and repo-scoped A2A server configuration with bearer, API key, mTLS, and OAuth2 client credentials auth.

Handler TUI connected to an A2A agent, showing the agent card and a completed assistant response

Install

Install Handler from the PyPI package as a uv tool:

uv tool install a2a-handler

Or with pipx:

pipx install a2a-handler

Or with pip:

pip install a2a-handler

Quick Start

Open the interactive terminal UI:

handler tui

Inspect an A2A server's agent card:

handler card get --url http://localhost:8000

Send a message from the CLI:

handler message send --url URL --text "hello"

Open the full documentation:

handler docs

Run Without Installing

Run Handler with uvx:

uvx --from a2a-handler handler

Run Handler with pipx:

pipx run a2a-handler

Documentation

Read the documentation at https://handler.alduncanson.com.