dsh-plugin-undo

Conversation undo for DeepSeek Harness: undo the last n turns within the current session — no new session, no project file changes.

Why this plugin

Most conversation-rewind plugins use sessions.fork to copy a history prefix into a new session (the original session is kept or archived). This plugin undoes in place on the current session's surface, so:

• No fork, no new session — the session id stays the same
• No duplicate “original + new” sessions in the sidebar
• You keep chatting in the same session, and the model context is exactly the retained history

Features

• /undo or /undo 1 — undo the last completed turn
• /undo 3 — undo the last 3 completed turns
• /undo all — undo every turn currently visible to the model

After undo:

• The model-visible history is replaced by the retained turns; undone turns leave the model context
• The raw session log stays append-only and is never rewritten
• The Web UI collapses the undone turns into a compact header
• The current session continues; no fork, no new session

Effect

Undone turns collapse in the chat view as:

↩ 第 N 轮已撤销 · 点击展开

Click the header to expand or collapse that turn in place. The /undo command card itself is hidden; the folded headers are the only visible undo feedback.

How it works

1. The host derives the currently model-visible turns from turn/start / turn/end
2. It takes the last n turns and appends surfaceOp: { op: 'replace', start, end } over their surface range
3. The checkpoint is an empty assistant message outside any turn boundary; message derivation skips empty assistant content, so the model sees only the retained history — no undo marker, no turn numbers
4. The client half reads the successful /undo command nodes and folds the undone turns with DOM/CSS

Install

dsh plugin --profile <profile> add file:/path/to/dsh-plugin-undo

Restart the profile:

dsh --profile <profile>

No additional configuration is required.

Usage

Type in the session input:

/undo
/undo 1
/undo 3
/undo all

The command requires the session to be idle. Stop the running turn first if the UI reports it is busy.

Build & pack

Published entry points live in lib/; source lives in src/. Build and create the distributable tarball:

npm run build
npm pack

This produces dsh-plugin-undo-<version>.tgz, which can also be installed directly:

dsh plugin --profile <profile> add file:/path/to/dsh-plugin-undo-<version>.tgz

Project layout

dsh-plugin-undo/
├── README.md
├── README_zh.md
├── cordis.patch.yml
├── package.json
├── scripts/
│   └── build.mjs
├── src/          # source
│   ├── index.js  # host: /undo command and surface replacement
│   └── client.js # web: folds undone turns, hides the command card
└── lib/          # build output (generated by npm run build)

License

MIT

Limitations

• Only consecutive trailing turns can be undone; picking an arbitrary message in the middle is not supported
• Only the model-visible conversation history is rewound; project files are never touched
• The session must be idle when /undo runs