Handler
Install
First commands
What to read next

Handler

Handler is an open-source A2A protocol client for the terminal. Use it when you want to:

send messages to A2A agents from a CLI
manage conversations and tasks in a terminal UI
inspect agent cards
expose an MCP server so your AI tooling can talk to A2A agents
save reusable server definitions with bearer, API key, mTLS, or OAuth2 auth

Install

uv tool install a2a-handler

Or with pipx or pip:

pipx install a2a-handler
# or
pip install a2a-handler

First commands

handler tui
handler message send URL "hello"
handler card get URL
handler mcp
handler server run agent

What to read next

Quickstart for the fastest path from install to first message
TUI and web UI for the interactive workflow
Messages, tasks, and sessions for the main CLI flow
MCP server to expose Handler to MCP-compatible tools
Local servers for the bundled test agent and webhook receiver
Servers for reusable server definitions
Authentication for bearer, API key, mTLS, and OAuth2 examples