agentclientprotocol/codex-acp

What it solves

This project provides a bridge between the Agent Client Protocol (ACP) and OpenAI Codex, allowing users to use Codex as an AI agent server. It translates ACP requests into Codex operations and maps Codex events back to the client, enabling a standardized way for ACP-compatible clients to interact with Codex's coding capabilities.

How it works

codex-acp acts as a stdio ACP agent server. It launches the Codex App Server and handles the translation of communication between the ACP client and the Codex backend. It supports multiple authentication methods (ChatGPT login, API keys, or custom gateways) and allows configuration of models, reasoning effort, and sandbox modes.

Who it’s for

Developers who use ACP-compatible clients and want to integrate OpenAI Codex for AI-assisted coding, shell command execution, and file management.

Highlights

• Multi-method Authentication: Supports ChatGPT login, API keys, and custom OpenAI-compatible gateways.
• Advanced Agentic Capabilities: Supports shell commands, file changes, MCP tool calls, and native ACP subagent sessions with separate histories.
• Session Management: Includes support for background terminal tasks, session-scoped long-running goals, and per-turn file-change reports.
• Extensible Tooling: Integrates with client-provided MCP servers via stdio or HTTP transport and supports various slash commands for status, review, and session management.