jupyterlab_ai_code_assistants_extension

A full launcher and manager for every AI code assistant in JupyterLab - Claude Code, Codex, Kimi and Gemini. Start, resume, fork, switch, and clean up CLI sessions from a side panel per assistant - one click lands you in the right terminal with the assistant already running, no duplicate tabs, no UUID hunting. One install replaces the separate jupyterlab_claude_code_extension, jupyterlab_codex_extension and jupyterlab_kimi_code_extension packages and migrates their settings and favourites automatically.

Why this extension

One principle: the vendors know best how to build the agent harness; we know best how to make it work in JupyterLab.

Chat-panel extensions re-implement the agent loop and trail the real tool. This one runs the genuine, unmodified CLIs in JupyterLab terminals - skills, subagents, MCP, hooks, plan mode, every release the day it lands. The extension owns the JupyterLab side:

• Launching - new, resumed, or forked sessions, with or without permission prompts, no wrapper shell, correctly sized before the assistant draws its first frame
• Finding - every project in one panel per assistant: favourites, search, live activity
• Reusing - clicking a session focuses its existing terminal, never a duplicate
• Managing - parallel conversations: switch, fork with a name, delete - no --resume pickers, no raw UUIDs

Features

• One install, every assistant - Claude Code, Codex, Kimi and Gemini from a single package, each with its own right-side panel wearing its official mark
• Provider registry - assistant-specific behaviour lives in one module per assistant behind capability flags; no core file names an assistant, and adding one touches no core file
• Joint settings page - one settings section covering all assistants, with a per-assistant toggle (all on by default); toggling takes effect live, no JupyterLab reload
• Three-section side panel - Favorites, Recent, and All projects, each scrolling independently
• One-click resume - click a row to jump back into that session in a terminal; an open terminal for the project is reused instead of duplicated
• Launcher tiles - every enabled assistant has a tile in an "AI Assistants" section of the JupyterLab Launcher (after Other, under the extension's own robot-head icon); a click opens the assistant in the file browser's current folder, resuming the folder's conversation when one exists and starting a new one otherwise, through the companion jupyterlab_basic_terminal_extension (installed automatically). Disable an assistant and its tile goes; disable them all and the section goes with them
• Your terminal's claude -c follows the panel (Claude) - switching to or launching a conversation makes plain claude -c in that project resume that same conversation, including one that has been compacted, which Claude Code otherwise refuses to continue
• Conversation switcher - a right-click "Switch and Manage Sessions" submenu lists a project's other conversations by name and short id with last-activity time; "Manage Sessions..." opens a searchable popup over the full list with multi-select delete and per-row open and copy-id buttons
• Branch session - fork the current conversation into a new named session via the right-click menu; each assistant forks its own way (Claude's native --fork-session, Codex's codex fork, server-side copies for Kimi and Gemini) behind the same menu item
• Launch modes under each assistant's own name - Claude's skip-permissions, Codex's approval bypass, Kimi's --yolo, Gemini's YOLO; unsafe variants carry a shield glyph in the launch menus
• Coloured terminal tabs - each session's colour tints its terminal tab via the companion jupyterlab_colourful_tab_extension (installed automatically). Claude's own /color supplies its default, Kimi derives a stable colour from the conversation id; Codex and Gemini have no colour of their own until you set one, and a branched session inherits its parent's colour, which it keeps even if the parent's colour later changes or is reset. Tinting needs the companion release that reports the colours you pick and lets another extension own a tab - against an older one this extension tints no tabs at all and says so once, and the companion's own right-click colours keep working as they always did
• Your own tab colour wins - set a colour on a terminal tab and the extension remembers it for that conversation, overriding whatever the assistant chose. Reset Tab Colour (n) in the session's right-click menu hands back every colour you set by hand on that project's conversations, and appears once there is one to hand back. Clearing the colour on the tab itself releases it too, for the conversation that terminal is running; Reset Tab Colour is the way back for a conversation with no tab open. A Codex or Kimi conversation that has never been resumed cannot be tracked yet, so a colour set on its tab is not kept
• Favorites - star projects you keep coming back to via the right-click menu; favourites from the standalone extensions are migrated on first run
• Remove and clean up - drop a project's history or a project's extra parallel sessions from the right-click menu, confirmation dialog first; removed files honour JupyterLab's "move files to trash" setting
• Activity at a glance - each row shows its last activity in an aligned column; rows active within the last minute light up, rows idle for over a week dim, and rows with parallel conversations show a branch icon with the count
• Remote control indicator and background agents (Claude) - a green dot marks sessions actively under remote control, and a conversation held by a running background agent shows a bg chip; clicking attaches to the agent instead of copying it
• Search - fuzzy filter per panel, toggled by the funnel button
• Presentation modes - label rows by session name or by path relative to the JupyterLab root
• Conflict-safe upgrade - if a retired standalone extension is still installed, its panel wins and this extension stands down for that assistant instead of showing a duplicate
• Auto-disabled when absent - an assistant whose CLI is not on PATH does not show a panel

Requirements

• JupyterLab >= 4.0.0
• Python >= 3.10
• At least one assistant CLI on PATH: claude, codex, kimi, or gemini

Install

Developers must install via the project Makefile (which orchestrates clean, build, and pip install of the resulting wheel):

make install

End-users can install the published package from PyPI:

pip install jupyterlab_ai_code_assistants_extension

[!WARNING] package.json pins webpack: 5.106.0 and chalk: 4.1.2 in both resolutions and overrides. Do not remove these. webpack >= 5.106.1 changed its module-federation share identifier format and crashes the unmaintained license-webpack-plugin (split('=')[1].trim()) that @jupyterlab/builder injects into every production build; the duplicate chalk@2.4.2 pulled by duplicate-package-checker-webpack-plugin crashes on Node 24+ in the build-isolation install. Without the pins, make publish and CI fail on python -m build.

Migrating from the standalone extensions

This package supersedes jupyterlab_claude_code_extension, jupyterlab_codex_extension and jupyterlab_kimi_code_extension. On first run it carries their settings and favourites over automatically; uninstall the standalones once you are ready:

pip uninstall jupyterlab_claude_code_extension jupyterlab_codex_extension jupyterlab_kimi_code_extension

Tab colours stored by versions of THIS extension before 1.0.0 are carried over and keep tinting their tabs, but Reset Tab Colour will not offer them: the store from that version cannot tell a colour you set from one a branch inherited, and offering the wrong one would strip a branch of the colour it was forked with. Set the colour on that tab once more and it becomes yours to reset.

While a standalone extension is still installed, its panel is shown and this extension's panel for that assistant stays out of the way.

Uninstall

pip uninstall jupyterlab_ai_code_assistants_extension