Notebook Cell Id

Point your coding agent at an exact notebook cell: "Review cell e66c99c5", "Fix cell 8d3f2a1c".

Every cell since nbformat 4.5 carries a stable id, but VS Code doesn't surface it anywhere in its UI. This extension puts it in each cell's status bar and makes it one click to copy.

Why

When you ask an agent (or a colleague) to fix or review one cell, referencing it by id beats every alternative:

• Accurate. The badge shows the same id field the agent sees when it opens the .ipynb JSON, so the reference resolves to exactly one cell. Ids survive re-ordering, inserting, and deleting cells — "the third code cell" and cell 3 don't.
• Token-efficient. 8 characters instead of pasting the cell's whole contents into the chat to identify it.
• Round-trippable. VS Code's ipynb serializer preserves ids on save, so the id you copied yesterday still points at the same cell today.

Features

• A right-aligned status bar item on every cell: ⧉ [#5](https://github.com/hannody/vscode-notebook-cell-id/issues/5) e66c99c5 (index + cell id).
• Click it to copy the id.
• Commands from the Command Palette, acting on the selected cell (the extension adds nothing to the cell toolbar or its ... menu — those stay exactly as VS Code ships them):
  • Notebook: Copy Cell Id → e66c99c5
  • Notebook: Copy Cell Id with Notebook Path → article_mat/v2_nb/step_3_.ipynb cell e66c99c5

Settings

Requirements

Cells only carry ids in nbformat 4.5 and newer. Older notebooks show no badge; re-saving them in a current Jupyter or VS Code will add ids. Works on jupyter-notebook and interactive documents.

How it works

VS Code's built-in ipynb extension deserializes the nbformat cell id onto NotebookCell.metadata.id, and writes it back on save. The extension reads that through a NotebookCellStatusBarItemProvider, so the badge tracks cells as you add, delete, and move them — no file parsing, nothing to keep in sync. Some older VS Code builds nested the value under metadata.custom.id; both are checked.

Development

git clone https://github.com/hannody/vscode-notebook-cell-id.git
cd vscode-notebook-cell-id
npm install          # only needed for the vsce/type devDependencies

Press F5 in VS Code to launch an Extension Development Host with the extension loaded, then open any .ipynb. Plain JavaScript, no build step.

To run it in your day-to-day VS Code instead, symlink the folder into your extensions directory and reload the window:

ln -sfn "$PWD" ~/.vscode/extensions/local.notebook-cell-id-0.1.0

License

MIT