agent-client-protocol 0.4.5

A Python implement of Agent Client Protocol (ACP, by Zed Industries)

Agent Client Protocol (Python)

Python SDK for the Agent Client Protocol (ACP). Build agents that speak ACP over stdio so tools like Zed can orchestrate them.

Each release tracks the matching ACP schema version. Contributions that improve coverage or tooling are very welcome.

Highlights

• Typed dataclasses generated from the upstream ACP schema (acp.schema)
• Async agent base class plus stdio transport helpers for quick bootstrapping
• Included examples that stream content updates and tool calls end-to-end

Install

pip install agent-client-protocol
# or with uv
uv add agent-client-protocol

Quickstart

1. Install the package and point your ACP-capable client at the provided echo agent:

   pip install agent-client-protocol
   python examples/echo_agent.py
   

2. Wire it into your client (e.g. Zed → Agents panel) so stdio is connected; the SDK handles JSON-RPC framing and lifecycle messages.

Prefer a step-by-step walkthrough? Read the Quickstart guide or the hosted docs: https://psiace.github.io/agent-client-protocol-python/.

Minimal agent sketch

import asyncio

from acp import Agent, AgentSideConnection, PromptRequest, PromptResponse, SessionNotification, stdio_streams
from acp.schema import AgentMessageChunk, TextContentBlock


class EchoAgent(Agent):
    def __init__(self, conn):
        self._conn = conn

    async def prompt(self, params: PromptRequest) -> PromptResponse:
        for block in params.prompt:
            text = getattr(block, "text", "")
            await self._conn.sessionUpdate(
                SessionNotification(
                    sessionId=params.sessionId,
                    update=AgentMessageChunk(
                        sessionUpdate="agent_message_chunk",
                        content=TextContentBlock(type="text", text=text),
                    ),
                )
            )
        return PromptResponse(stopReason="end_turn")


async def main() -> None:
    reader, writer = await stdio_streams()
    AgentSideConnection(lambda conn: EchoAgent(conn), writer, reader)
    await asyncio.Event().wait()


if __name__ == "__main__":
    asyncio.run(main())

Full example with streaming and lifecycle hooks lives in examples/echo_agent.py.

Examples

• examples/mini_swe_agent: bridges mini-swe-agent into ACP, including a duet launcher and Textual TUI client
• Additional transport helpers are documented in the Mini SWE guide

Documentation

• Project docs (MkDocs): https://psiace.github.io/agent-client-protocol-python/
• Local sources: docs/
  • Quickstart
  • Mini SWE Agent bridge

Development workflow

make install                     # create uv virtualenv and install hooks
ACP_SCHEMA_VERSION=<ref> make gen-all  # refresh generated schema bindings
make check                       # lint, types, dependency analysis
make test                        # run pytest + doctests

After local changes, consider updating docs/examples if the public API surface shifts.