dsh-chatgpt-web: Reusing ChatGPT Web Sessions via a Local Chrome Extension

Introduction¶

The core architecture of DeepSeek Harness (DSH) is modular. When using models or interfaces from ChatGPT Web, an API key or Secure MCP Tunnel is typically required. dsh-chatgpt-web provides an alternative that does not require these external dependencies: it leverages a local Chrome extension to take over an already logged-in ChatGPT session in the user’s browser and use it as a data source for DSH.

What It Is¶

This is an experimental standalone DeepSeek Harness provider, maintained by NishiMihaeru. It connects to an authenticated ChatGPT Web session through a local Chrome extension. The native DSH chat interface communicates with the extension via a local WebSocket bridge, controlling a dedicated ChatGPT Worker Tab.

Core Features¶

The plugin implements the following features:
* Text Provider: Provides the chatgpt-web/auto data source; currently only supports text input/output.
* Session Management: Each DSH session corresponds to a ChatGPT conversation created by the plugin and managed by the extension.
* Dedicated Tab: The extension opens a dedicated Chrome Worker Tab to handle generation requests.
* FIFO Serialization: The output of browser-generated content follows the first-in, first-out (FIFO) principle.
* Interruption Synchronization: Cancellation operations in DSH trigger ChatGPT to stop generating.
* Persistent Mapping: The mapping between DSH session IDs and ChatGPT URLs, along with synchronization summaries, is persisted.
* Recovery Mechanism: If the managed ChatGPT conversation is found to be missing before sending, a safe recovery can be performed.
* Context Awareness: Runtime context-aware response positioning prevents DSH plugin snapshots from being mistaken for user requests.
* Authentication: Validates stable Chrome extension identity and Origin on the loopback bridge.

Installation and Enablement¶

Installing the plugin requires DeepSeek Harness 0.1.1-rc.2 and Node.js ^22.19.0 || >=24.0.0 version requirements.

Use the official installation command:

dsh plugin --profile web add dsh-chatgpt-web

Enable the Chrome extension:
1. Open chrome://extensions.
2. Enable Developer mode.
3. Click Load unpacked extension.
4. Select the plugin’s extension directory.

Select in DSH:

chatgpt-web/auto

Then use the normal DSH chat interface.

Use Cases and Cautions¶

Environment Requirements: An external Chrome/Chromium browser is required with the unpacked extension installed.
Text Limitations: The current version only supports text input/output and does not support tool calls (although tool modes may be received, they cannot be executed on the ChatGPT side).
Parameter Limitations: reasoningEffort, temperature, maxTokens, stop, and DSH-assisted purpose calls are all rejected because ChatGPT Web does not support these parameters.
Output Semantics: Browser delta events are only observed as internal transport and are not sent to DSH as user-visible incremental text. Text is only emitted as a complete text block upon generation-complete, which means the v0.1 version sacrifices token-by-token streaming to ensure correctness.
Maintainability: Changes to the DOM of ChatGPT Web may require updating extension/chatgpt-page-adapter.js.

Summary¶

dsh-chatgpt-web allows developers to run DSH using their existing ChatGPT Web account without an OpenAI API Key. It achieves session reuse and interruption synchronization through a local extension bridge. However, in the v0.1 version, it is a feature-limited text-only provider and is quite sensitive to the browser environment and the DOM structure on the ChatGPT side.