Introduction

DeepSeek Harness (DSH) supports native extensions through Profile Bundles. dsh-gpt56-ptc is a plugin maintained by community developer Exception-H. It creates a genuine custom preset named GPT-5.6 PTC in the DSH user preset root. The plugin aims to provide cache-stable, pure PTC (Pure Tool Call) / Code Mode sessions for the gpt-5.6-sol, gpt-5.6-terra, and gpt-5.6-luna models, reducing scope expansion and verification loops within sessions through static constraints.

Plugin Information

  • Name: dsh-gpt56-ptc
  • Category: Model Inference
  • Maintainer: Exception-H
  • License: MIT
  • Current Status: Experimental v0.1.2 (for DSH 0.1.0-rc.8)
  • Notes: Unofficial community project; not reflective of DeepSeek’s official position.

Installation

Before installing, ensure the environment meets the following requirements:
* DeepSeek Harness version 0.1.0-rc.8
* Node.js version 20 or higher
* pnpm is installed in the system PATH, and the dsh plugin command is available

Install it using one of the following commands:

# 在本地目录安装
dsh plugin --profile web add .

# 安装固定的 Release 产物
dsh plugin --profile web add https://github.com/Exception-H/dsh-gpt56-ptc/releases/download/v0.1.2/dsh-gpt56-ptc-0.1.2.tgz

# 安装固定 Git Tag
dsh plugin --profile web add github:Exception-H/dsh-gpt56-ptc#v0.1.2

After installation, restart the DSH Web Profile. The installer automatically completes preset creation and validation.

Core Features

  1. Create user preset: Creates a custom preset named gpt56-ptc in the DSH user preset root.
  2. Model support: Supports gpt-5.6-sol, gpt-5.6-terra, and gpt-5.6-luna.
  3. In-session pinning: Users manually select the model when creating a session, and the model remains fixed within that session.
  4. Preserve official composition: Retains the full tool set and composition of the official Code preset.
  5. Static constraints: Provides a static persona and a minimal trajectory-control contract to prevent scope expansion.
  6. Pure PTC / Code Mode: Defaults to pure tool-call mode, without Native/PTC switching or per-turn tool pruning.

Usage

  1. Restart the DSH Web Profile.
  2. Create a new session and select GPT-5.6 PTC from the preset list (usually shown as “Custom”).
  3. Manually specify the model to use, for example gpt-5.6-sol, gpt-5.6-terra, or gpt-5.6-luna.
  4. Keep the model unchanged in the current session; if you need to switch models, create a new session or fork the session.

Notes

  • Experimental: The current version is experimental 0.1.2, and functionality may differ in future versions.
  • No base-capability configuration: This plugin does not configure Providers, API Keys, default models, Sandboxes, or approval policies; these remain managed by the DSH Host.
  • Copy snapshots: Installation and updates do not silently refresh user copies, preserving local user modifications.
  • Uninstall retention: Uninstalling the Bundle does not delete the installed gpt56-ptc custom preset.
  • Dependency environment: The installer depends on the pnpm hoisted Profile structure created in rc.8.

Access