A2A Adapter: developer tool for Hermes Agent

Python SDK and CLI that expose Hermes Agent, Claude Code, Codex and other agents as A2A protocol servers

What A2A Adapter does

A2A Adapter wraps agent CLIs, local agents, workflow engines and Python agent frameworks behind the A2A (Agent-to-Agent) Protocol. It generates the AgentCard and handles JSON-RPC, task lifecycle and streaming through the official A2A SDK, so an adapter only needs to invoke the underlying agent. The server publishes its card at /.well-known/agent-card.json.

There are two ways to use it. The CLI exposes an already installed local agent from the current directory without writing Python, with examples for Pi, Codex, Claude Code and OpenClaw, and options after a double dash are passed through to the agent CLI. The Python SDK ships adapters for Claude Code, Codex, Pi, OpenClaw, n8n, LangGraph, LangChain, CrewAI, Ollama, Hermes Agent, plain Python callables and a base class for custom adapters. The Hermes Agent adapter, HermesAdapter, is listed with streaming support and has an example script, hermes_agent.py.

Key features

Python SDK with a HermesAdapter that supports streaming
Automatic AgentCard generation at /.well-known/agent-card.json
CLI that serves local agents such as Pi, Codex, Claude Code and OpenClaw as A2A servers
Adapters for n8n, LangGraph, LangChain, CrewAI and Ollama
CallableAdapter and BaseA2AAdapter for custom agents
JSON-RPC, task lifecycle and streaming through the official A2A SDK

When to use it

Making a Hermes Agent reachable by other agents over the A2A protocol
Letting agents built on different frameworks call one another
Wrapping a plain Python function as an A2A server for testing

Who it is for: Developers building multi-agent systems who need agents from different frameworks, including Hermes Agent, to talk through the A2A protocol.

How it fits with Hermes Agent

Supports Hermes Agent among many frameworks through a HermesAdapter in its Python SDK.

How to install A2A Adapter

These commands are copied from the project's README. Check the repository for the latest steps before you run them.

pip install a2a-adapter

FAQ

What is A2A Adapter?

A2A Adapter is an open-source Python SDK and CLI that exposes an AI agent as an A2A Protocol server. It handles the AgentCard, JSON-RPC, task lifecycle and streaming so only the call into the underlying agent has to be written.

Does A2A Adapter work with Hermes Agent?

Yes. The Python SDK includes HermesAdapter, listed with streaming support and an example in examples/hermes_agent.py.

How do I install A2A Adapter?

Run pip install a2a-adapter. The package provides the a2a-adapter command-line tool as well as the Python SDK.