Codex Mode for DeepSeek Harness

A Codex-style execution mode for DSH. It adds a switch at the top of the
permission menu, keeps a durable plan, emits visible progress while tools run,
and continues a turn that stops with unfinished work.

The important difference from a prompt-only mode: if the model emits a tool call
without text, the host driver commits a short progress message before the
tool runs, as part of the durable assistant message. A long turn is not a silent
tool loop.

What it does

• Codex switch at the top of the permission menu, above a divider. The
  switch does not change the sandbox or approval level.
• Remembered globally: the last state is stored in the profile's
  codex_mode storage domain. Turning it on or off applies to every live root
  session; new and resumed sessions inherit it automatically.
• Visible progress before every tool batch. The model's own commentary is
  kept; a missing one is inserted by the driver in the user's language.
• Turn continuation when the todo list still has unfinished work and the
  assistant is not asking a question.
• Durable per-session identity stored as codex-read-only,
  codex-workspace-write, or codex-danger-full-access, so the mode appears in
  the session log and survives resume.
• Same safety gates for Full access and Auto review as the stock permission
  control.

Requirements

• DSH Desktop or Web with the Plugin Manager. Tested with DSH 0.2.1-rc.3.
• The package declares engines.dsh: ^0.2.1-rc.1; install it on a 0.2.1-rc.x
  runtime.
• Git and network access to GitHub for the first install.

Install

Option 1: give DSH the GitHub link

Start a new DSH session and send:

Install this DSH plugin bundle from GitHub: https://github.com/airainal/dsh-codex-mode

The agent can call the plugin_manager tool with that URL. The manager checks
the GitHub repository, installs the bundle, and enables it. You can also open
Plugins → Install bundle and paste:

https://github.com/airainal/dsh-codex-mode

If your DSH version wants an explicit git spec, use:

github:airainal/dsh-codex-mode

Option 2: install the release tarball

Download the asset from
Releases and paste either
the release asset URL or the downloaded .tgz path into Plugins → Install
bundle:

https://github.com/airainal/dsh-codex-mode/releases/download/v1.1.0/dsh-codex-mode-1.1.0.tgz

After installing

1. Open any session.
2. Click the permission control at the bottom of the composer.
3. Turn on Codex Mode at the top of the menu.
4. Pick Read Only, Workspace Write, or Full access exactly as before. The
   mode and the permission level are independent.

HMR applies the change immediately in the desktop app. If your profile has HMR
disabled, restart DSH after installation.

To remove it, open Plugins → Codex Mode → Remove, or ask the agent to remove
the bundle.

Use

The menu has two dimensions:

• the Codex switch controls the execution protocol;
• the permission choices control the sandbox and approval policy.

Turning Codex on while Workspace Write is selected moves every live root
session to its matching codex-workspace-write identity, but each sandbox stays
workspace-write. The last switch state is remembered; a new or resumed session
is moved to its matching codex-* identity automatically. Changing permission
while the mode is on keeps the global mode and changes only that session's
permission base.

The same toggle is available as a Host command:

/codex-mode on
/codex-mode off

Auto review is disabled while Codex is on because there is no codex-auto
identity. Turn Codex off first if you want Auto review.

The trigger shows a Codex mark on the right when the mode is on. It slides out
with a 240 ms width/opacity transition, and the menu stays open while switching.

How it works

The package is a DSH bundle with a Host half and a Web client half.

• cordis.patch.yml adds the three codex-* permission presets and mounts the
  Host plugin.
• A profile-level codex_mode storage domain keeps { enabled, updatedAt }.
  The /codex-mode on|off command writes it first, then applies the matching
  codex-* or base preset to every live root session. The agent/created
  listener applies the remembered value to new and resumed root agents.
• The Host plugin adds the codex:mode system-prompt section and wraps each
  live agent's step. In Codex mode, an assistant/message that contains only
  tool calls gets a leading progress text block before it is committed; the
  matching text-chunks record is added to the stream and tool-call block
  indexes are shifted so content and stream stay aligned.
• agent/turn-stopping provides one continuation steer when the plan is
  unfinished and the reply is not a question.
• The Client plugin replaces the current-session permission control with the
  same control plus the Codex row, keeping the original permission glyphs and
  the Full-access/Auto-review risk dialogs.

This is a Codex step driver, not a second tool runtime. DSH still owns turn
construction, tool dispatch, approvals, retries, compaction, and the event log.
A full fork of those systems would duplicate a large amount of tested
infrastructure; the driver changes the part users actually see: progress output
and turn continuation.

Why the progress line is provable

The line is not a UI status chip. In a test turn that explicitly told the model
not to emit text, the model's stream contained only reasoning and tool-call
chunks, with no text-chunks. The committed assistant message was:

[reasoning, "我先读取 `dsh-codex-mode/client.js`。", tool-call]

The matching stream indexes were reasoning 0, text 1, tool-call 2. The
text could only come from the Host driver. The test was run locally against DSH
0.2.1-rc.3; the session log itself is not published.

Scope and limitations

• The package targets DSH 0.2.1-rc.x. It uses the live agent's step and the
  session append boundary; a future DSH release can change those internals.
• It is not a complete Codex engine. Freeform apply_patch, Codex-style
  one-tool scheduling, shell/output limits, and Codex compaction thresholds are
  not implemented.
• The bundle overrides the permission row to add the codex-* presets. If you
  maintain custom permission presets in a profile, carry them into
  cordis.patch.yml before installing.
• The built-in /permission command also lists the codex-* identities. Use the
  composer menu or /codex-mode on|off for the global switch; a direct
  /permission change is a per-session override.
• The Settings default-permission selector lists the codex-* presets because
  they are ordinary permission presets; the composer menu is the intended place
  to switch a running session.

Screenshots

Development

There is no build step.

git clone https://github.com/airainal/dsh-codex-mode.git
cd dsh-codex-mode

Install the directory as a bundle through Plugins → Install bundle, or ask a
DSH agent to install that path with plugin_manager. The Host plugin exports
apply(), the client is a plain window.__ModuleLoader__ module, and the bundle
patch is cordis.patch.yml.

To build the release tarball:

pnpm pack

中文快速安装

把下面这句直接发给新的 DSH 会话：

安装这个 DSH 插件 bundle：https://github.com/airainal/dsh-codex-mode

装好后打开任意会话，点输入框下方的权限按钮，在菜单顶部打开 Codex 模式。
开关状态会被记住并同步到所有会话，新会话自动继承；权限级别不会改变。

License

MIT. See LICENSE.