DeepSeek Harness — Session Split Screen

An iTerm-style session multiplexer for the DeepSeek Harness Web GUI. It puts several Harness sessions on one screen and lets each pane point at a different workspace.

Features

• Nested vertical (side-by-side) and horizontal (stacked) splits.
• Drag any divider to resize adjacent panes.
• Drag one pane header onto another to swap their sessions.
• Up to 12 panes in one layout.
• Native sidebar session selection: focus a pane, then choose its session from the standard Harness session list.
• Switching sessions keeps the Split tab open and assigns the selected conversation to the focused pane.
• Live streaming transcript, session status, queued replies, stop action, and older-history loading in every pane.
• Structured-input indicator for approvals, plan review, and questions, with a jump to the full Harness view.
• Layout, split ratios, pane order, selected session ids, and unsent pane drafts persist in browser localStorage.
• Native Split conversation tab, Chinese and English UI tied to the Harness locale, dark-theme token compatibility, and keyboard controls.

Install

From npm after publication:

dsh plugin --profile web add @syncended/dsh-split-screen

From this checkout during development:

dsh plugin --profile web add /home/syncended/deepseek-harness-split-screen

Some pnpm-backed profiles require the workspace-root flag:

dsh plugin --profile web add -w /home/syncended/deepseek-harness-split-screen

Restart dsh web after first installation and refresh the existing Web GUI. A native Split tab appears beside the conversation's other views.

Usage

1. Open any non-blank session and select the native Split conversation tab.
2. Select a pane by clicking it.
3. Use Split vertically or Split horizontally in the active pane header.
4. With the target pane focused, choose any session in the native sidebar. The Split tab stays open and the selected session is attached to that pane.
5. Use the standard New Session action when you need another conversation. Resize with the divider or drag one pane header onto another to swap their contents.
6. Select the native Chat tab to return to the full Harness conversation view.

Keyboard shortcuts

Shortcut	Action
Alt+Shift+V	Split the active pane vertically
Alt+Shift+H	Split the active pane horizontally
Enter	Send from the focused composer
Shift+Enter	Insert a newline

Workspace behavior

A single dsh web Host exposes all workspaces registered in that profile. The plugin can mix their sessions freely in one layout; panes do not have to share a cwd or repository.

This version does not aggregate sessions from separate DSH server processes or different remote URLs. Those are separate Hosts and would require a multi-connection runtime rather than a client layout plugin.

Development

npm run check
npm test
npm pack --dry-run

The package has two runtime faces:

• lib/index.js — no-op Host loader entry.
• lib/client.js — dependency-free DSH lazy client module.

The browser half uses supported public seams:

• ctx.slots.inject("conversation.view", ...) for an additive native conversation tab.
• ctx.sessions.list, open(id), and binding(id).session for native selection tracking, history, streaming, prompts, cancellation, and paging.
• ctx.workspaces.list for native workspace and session labeling.

The layout is a persisted binary tree. Split nodes own direction and ratio; leaf nodes own stable pane ids and optional session ids. Removing a leaf collapses its parent, while header drag-and-drop swaps leaf session assignments without rebuilding the tree.

Current limitations

• The compact panes intentionally render conversational text and compact tool/command rows, not the full Harness card registry.
• Structured approvals, plan review, and ask_user_question must be completed in the normal main view; the pane provides a direct jump there.
• Attachments can be represented in history, but this first version sends text prompts only.
• Browser persistence is local to the current origin/profile.

Requirements

• DeepSeek Harness 0.1.0-rc.6 or compatible.
• The Web profile (dsh web).
• Node.js 18 or newer.

License

MIT — see LICENSE.