dsh-codex-mode

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

Menu, light · Trigger ·

Dark risk gate · Narrow layout ·

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: