The guiding principle of DeepSeek Harness (DSH) is “everything is a plugin.” When debugging reasoning models, manually adjusting the reasoning level (off / minimal / low / medium / high / xhigh / max) often requires changing settings or multiple clicks. The dsh-reasoning-slider plugin embeds a reasoning-level slider, similar to Codex’s, directly into DSH’s model selector, allowing level adjustments to be completed at the UI level.

This is a DSH plugin maintained by edwardzhou21 and licensed under MIT. It does not change the model logic; instead, it encapsulates the reasoning-level switching logic through UI interactions, making it possible to adjust the level directly within the model selector.

Core Features

  • Embedded display: The slider is located in the model selector popup. After selecting a model, it automatically displays the reasoning levels supported by that model.
  • Real-time preview: Drag the slider to preview changes in real time; the selected level takes effect after release.
  • Smart level retention: When switching models, the plugin attempts to retain the current level; if the target model does not support that level, it automatically falls back to its default level.
  • Multimodal interaction: Supports switching levels using the keyboard (←/→ or ↑/↓) and the mouse wheel.
  • Status hints: Models with a single reasoning level display “Supported level: xxx”; models with no reasoning levels display a notice.

Installation and Enablement

You need to install pnpm and DSH. Here is the installation command using the desktop profile:

dsh plugin --profile desktop add https://github.com/edwardzhou21/dsh-reasoning-slider/archive/refs/tags/v0.0.7.tar.gz

After installation, open the model selector in the DSH UI to see the plugin.

Typical Usage

  1. Open DSH and click the model selector.
  2. Select a model.
  3. Drag the slider that appears below to adjust the reasoning level.
  4. Release the mouse, and the level takes effect immediately.

Use Cases and Notes

  • Use cases: Suitable for developers who need to frequently test different reasoning levels. For example, comparing the output quality of a low level and the maximum level.
  • Notes:
    • Environment requirements: The plugin requires Node.js version 22.13.0 or higher.
    • DSH compatibility: dsh-reasoning-slider@0.0.7 supports DSH versions 0.1.2-alpha.2, 0.1.2-alpha.4, 0.1.2-alpha.5, 0.1.2-rc.1, and 0.2.0-rc.2; DSH 0.1.2-alpha.3 has not been verified yet.
    • npm package differences: The reasoning-slider package on npm is the upstream original version and does not include the changes from this repository.

The plugin is integrated through the Cordis patch mechanism, with the source code located on GitHub.