A2A Adapter

Expose your AI agent as an A2A Protocol server in a few lines of Python.

a2a-adapter wraps agent CLIs, local agents, workflow engines, and Python agent frameworks behind the A2A (Agent-to-Agent) Protocol. It handles AgentCard generation, JSON-RPC, task lifecycle, and streaming through the official A2A SDK, so your adapter only needs to invoke the underlying agent.

Works with Claude Code, Codex, Pi, OpenClaw, n8n, LangGraph, LangChain, CrewAI, Ollama, Hermes Agent, and custom Python functions.

Install

pip install a2a-adapter

CLI Use Case

Use the CLI when you want to expose an already installed local agent from the current terminal directory without writing Python:

a2a-adapter pi --port 9012
a2a-adapter codex --port 9011
a2a-adapter claude --port 9010
a2a-adapter openclaw --port 9008

Options before -- configure the A2A server. Options after -- are passed to the underlying agent CLI:

a2a-adapter pi --port 9012 -- --model <model> --thinking high
a2a-adapter codex --port 9011 -- --model <model> --sandbox workspace-write
a2a-adapter claude --port 9010 -- --model <model>
a2a-adapter openclaw --port 9008 --agent-id main --thinking high

Use --cwd /path/to/project to choose another working directory and --host 0.0.0.0 when the server must be reachable outside the local machine. Pi source commands can be selected without a shell wrapper:

A2A_PI_COMMAND='npx tsx /path/to/pi/packages/coding-agent/src/cli.ts' \
  a2a-adapter pi --port 9012

Run a2a-adapter -help for the supported agents, or a2a-adapter <agent> -help for agent-specific usage. The adapter owns protocol and session flags such as Pi's --mode rpc and Codex's --json; those flags cannot be overridden after --.

Python SDK Use Case

Use the Python SDK when embedding A2A support in an application, wrapping a Python framework, or providing custom adapter configuration:

from a2a_adapter import CallableAdapter, serve_agent

adapter = CallableAdapter(func=lambda inputs: f"Echo: {inputs['message']}", name="Echo")
serve_agent(adapter, port=9000)

The SDK produces the same A2A server and auto-generated AgentCard:

http://localhost:9000/.well-known/agent-card.json

Supported Python SDK Adapters

Documentation

• Quick Start - end-to-end setup and testing guide
• Examples - runnable examples for each adapter
• Architecture - SDK delegation, request flow, and internals
• Changelog - release notes and migration history
• Contributing - development setup and contribution guide

Star History

License

Apache-2.0 - see LICENSE.

Built by HYBRO AI. Powered by the A2A Protocol.