Introduction

DeepSeek Harness (DSH) is a developer-facing tool that provides core capabilities such as conversation, workspace, and tool management. For users who need to use Codex models within DSH, invoking Codex while keeping the DSH interface smooth can avoid frequent switching between clients or maintaining additional code branches. relay-dsh-plugin-codex is designed to achieve this goal.

Plugin Overview

  • Name: relay-dsh-plugin-codex
  • Maintainer: yangbobo2021
  • Category: Model Inference
  • License: MIT

This plugin provides DSH with a native Codex conversation backend, running through Codex App Server while preserving DSH’s session management, workspace, and tooling support.

Core Features

  • Native Codex Backend: Directly integrates Codex as a conversation backend in DSH.
  • Preserved DSH Context: Retains DSH’s workspace, conversation history, editor, approvals, and tools.
  • Session Association: Each DSH session corresponds to one Codex App Server thread, ensuring conversation continuity.
  • Unified Conversation: You can use the Codex model, reasoning capabilities, images, interruption mechanisms, and tools contributed by DSH within the same conversation.

Installation and Activation

Before installing, make sure the environment meets the requirements:

  1. Environment Requirements:

    • Node.js 22.13 or later
    • pnpm has been added to the system PATH

  2. Run Installation:
    Use the officially provided command to install the latest stable version:

    npx @deepseek-ai/dsh@0.1.2-rc.1 plugin --profile web add relay-dsh-plugin-codex@latest
  1. Start DSH:
    npx @deepseek-ai/dsh@0.1.2-rc.1 web

Typical Usage

Before using the plugin, complete Codex authentication.

  1. Authentication:
    Before creating the first session, make sure you are signed in via the official Codex client. When using the CLI, you can run:
    codex login
  1. Create a Session:
    Open DSH, click New Session, select a workspace, choose Codex from the mode menu, and then send a message.

Use Cases and Limitations

Use Cases:
* You need to use the Codex model inside DSH and avoid switching user interfaces.
* You want to retain DSH’s native conversation history, editor, and tool capabilities.
* You need to mix the Codex model and DSH tools within the same conversation.

Known Limitations and Notes:
* DSH Status: DSH is currently in developer preview and may introduce breaking compatibility changes.
* Features Not Included: This plugin does not add Relay Events, file browsing, or a terminal panel.
* Known Issue: Empty local command events may occasionally occur.
* Feature Differences: Full desktop feature parity is not provided.

Summary

This plugin integrates Codex App Server, enabling DSH users to use Codex’s reasoning capabilities in the same environment while maintaining their existing DSH workflow habits. The related source code and directory page can be found via the links below.