Introduction

The web client of DeepSeek Harness has built-in model selection, but for users who need fine-grained control over thinking levels or prefer desktop-style UI interactions, the existing controls may not be intuitive enough. This article introduces a plugin that replaces the web composer’s model selector with a control panel closer to the ChatGPT desktop version.

What It Is

dsh-client-ui-gpt-helper is a DeepSeek Harness client (browser) plugin, authored by AprilCrystal, and licensed under the MIT License. Its core purpose is to replace the model selection control in the web composer, providing a grouped list, a thinking-level slider with particle trails, and a lightning mode toggle.

Core Features

  1. Model selection: Uses the real model directory, grouped by provider, and supports search (can search the first 4 entries).
  2. Thinking level slider: Converts the selected model’s advertised levels into ticks on the slider, with particle-trail animation. Supports dragging, clicking ticks, or using arrow keys, and the value snaps to the nearest level.
  3. Lightning mode: Provides a visual lightning mode toggle, also with particle-trail animation. Turning it on lights up the trail, while turning it off slows it down and extinguishes it.
  4. Mode lock: Hold the lightning icon for 600 milliseconds to lock the mode. When locked, the icon becomes lock-shaped, and the locked state persists after refreshing the page or restarting the app. Hold it again for 600 milliseconds to unlock.
  5. Theme configuration: Press Ctrl+Shift+Alt+G to open a color panel for customizing the control’s colors without modifying the source code.

Installation and Enabling

Prerequisites

You need to have the DeepSeek Harness web client running (using the desktop profile or any profile that has @deepseek-ai/dsh-web-app mounted).

Installation Steps

This plugin is a DSH bundle. Its package.json declares dsh.bundle.patch, and cordis.patch.yml is handled automatically during installation.

Install by package name:

dsh plugin --profile <profile> add dsh-client-ui-gpt-helper

Install by local path:

dsh plugin --profile desktop add /absolute/path/to/dsh-client-ui-gpt-helper

How It Works

The plugin overrides the default model selection control by registering the conversation.input.model single slot with negative priority. It reuses the default control’s ctx.modelDirectories service and the /model command, ensuring the data layer remains in sync.

Typical Usage

After installation, a new control panel appears in the web composer area:
* Adjust thinking level: Drag the slider or use arrow keys to adjust the level of thinking.
* Toggle lightning mode: Click the lightning icon to switch modes, or hold it for 600ms to lock.
* Switch models: Click the model name to open the model list, or press Ctrl+Shift+Alt+G to open the color panel.

Applicable Scenarios and Notes

This plugin is suitable for DSH web users who want an experience closer to that of a desktop client, especially in scenarios with clear needs for model selection and thinking-level control.

Notes:
* The plugin does not require a build step; the files are already packaged.
* It directly replaces the composer control included with DSH, rather than displaying alongside it.
* Lightning mode currently provides visual effects only; DSH itself does not have this concept.

Short Conclusion

By reusing the data layer and replacing the UI rendering layer, the plugin delivers more precise control and visual feedback without changing the core logic of DSH. The related code and documentation can be found in the GitHub repository or the SkillHub plugin directory.