Your terminal workspace has a new roommate. Press Alt+j and tell it what you need.

Jelly J is a Claude-powered assistant that lives inside Zellij. Instead of memorizing keybindings, you just talk to it — "create a tab for logs", "split this into three panes running htop, kubectl, and lazygit", "name all my unnamed tabs based on what's running in them".

It sees your entire workspace layout, understands what's running where, and reorganizes things on your behalf. It even checks in every 5 minutes to suggest improvements (like a tidy roommate, not an annoying one).

What it can do

• Name things — tabs and panes, based on what's actually running
• Rearrange — move, resize, float, stack, fullscreen any pane
• Create — new tabs and panes running any command
• Inspect — dump the full layout, list tabs, show what's connected
• Tidy up — the heartbeat checks for unnamed tabs, overcrowded layouts, idle panes
• Escape hatch — run any zellij action subcommand directly

Quick start

Prerequisites

• Zellij (v0.40+)
• Node.js (v18+)
• Claude Code CLI (authenticated — Jelly J uses the Agent SDK which requires a valid Claude Code session)

Install & run

# Try it (downloads, runs, cleans up)
npx jelly-j

# Install globally
npm install -g jelly-j
jelly-j

# Or clone for development
git clone https://github.com/victorarias/jelly-j
cd jelly-j && npm install && npm start

Zellij keybinding (optional)

Add to your ~/.config/zellij/config.kdl to launch Jelly J with Alt+j:

keybinds {
    shared {
        bind "Alt j" {
            Run "npx" "jelly-j" {
                direction "Down"
                close_on_exit true
            }
        }
    }
}

Or as a floating pane:

keybinds {
    shared {
        bind "Alt j" {
            ToggleFloatingPanes
            Run "npx" "jelly-j" {
                floating true
                close_on_exit true
                name "Jelly J"
            }
        }
    }
}

Fish shell function (optional)

function jj --description "Launch Jelly J in a floating Zellij pane"
    zellij action new-pane --floating --name "Jelly J" --close-on-exit -- npx jelly-j
end

How it works

┌──────────────────────────────────────────┐
│  Zellij Session                          │
│                                          │
│  ┌─────────┐  ┌─────────┐  ┌─────────┐  │
│  │  Tab 1  │  │  Tab 2  │  │  Tab 3  │  │
│  │ ┌─────┐ │  │ ┌─────┐ │  │ ┌─────┐ │  │
│  │ │pane │ │  │ │pane │ │  │ │pane │ │  │
│  │ ├─────┤ │  │ └─────┘ │  │ └─────┘ │  │
│  │ │pane │ │  │         │  │         │  │
│  │ └─────┘ │  └─────────┘  └─────────┘  │
│  └─────────┘                             │
│                                          │
│  ┌─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─┐  │
│    Jelly J (floating pane)               │
│  │ ❯ name all my tabs                 │  │
│    [zellij] get_layout                   │
│  │ [zellij] rename_tab name="logs"    │  │
│    [zellij] rename_tab name="deploy"     │
│  │ Done! Named 3 tabs based on ...    │  │
│  └─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─┘  │
└──────────────────────────────────────────┘
         │                    ▲
         │  User prompt       │  Tool calls
         ▼                    │
   ┌───────────┐        ┌─────────┐
   │  Claude    │───────▶│  Zellij │
   │  Opus 4.6 │  MCP   │  CLI    │
   └───────────┘        └─────────┘
         │
    Heartbeat (every 5m)
         │
   ┌───────────┐
   │  Claude    │──▶ Popup suggestion
   │  Haiku 4.5│     (floating pane)
   └───────────┘

• REPL: readline prompt in a floating Zellij pane
• Agent: Claude Opus 4.6 via the Agent SDK
• Tools: 20 MCP tools wrapping zellij action subcommands
• Heartbeat: Haiku 4.5 checks workspace state every 5 minutes, shows popup suggestions

Tools

Workspace state

| Tool | What it does | |------|-------------| | get_layout | Dump the full layout as KDL — tabs, panes, IDs, commands, positions | | list_tabs | List all tab names in the session | | list_clients | List connected clients, focused panes, running commands |

Tab management

| Tool | What it does | |------|-------------| | go_to_tab | Switch by index or name, optionally create if missing | | new_tab | Create a tab with optional name, cwd, layout | | close_tab | Close the focused tab | | rename_tab | Rename the focused tab |

Pane management

| Tool | What it does | |------|-------------| | new_pane | Open tiled, floating, or stacked pane with optional command | | close_pane | Close the focused pane | | rename_pane | Rename the focused pane | | move_focus | Move focus in a direction | | move_pane | Move the focused pane | | resize_pane | Resize the focused pane | | toggle_floating_panes | Show/hide all floating panes | | toggle_pane_embed_or_floating | Convert floating ↔ tiled | | toggle_pane_pinned | Pin/unpin a floating pane | | toggle_fullscreen | Toggle fullscreen | | change_floating_pane_coordinates | Reposition/resize a floating pane by ID | | write_to_pane | Send keystrokes to the focused pane |

Escape hatch

| Tool | What it does | |------|-------------| | zellij_action | Run any zellij action subcommand directly |

Heartbeat

Every 5 minutes (after an initial 2-minute delay), Jelly J quietly checks your workspace using Haiku 4.5. If it spots something worth mentioning — like a bunch of unnamed tabs, an overcrowded layout, or idle panes — it pops up a short suggestion in a floating pane that auto-closes after 30 seconds.

It skips checks while you're actively chatting, so it won't interrupt you.

Cost

Main interactions use Claude Opus 4.6 (priced per conversation turn). Heartbeat uses Claude Haiku 4.5 (~$0.001/check × 12/hour × 8 hours ≈ $0.10/day).

Development

git clone https://github.com/victorarias/jelly-j
cd jelly-j
npm install

# Run from source (uses tsx)
npm start

# Type-check
npm run typecheck

# Build for distribution
npm run build

# Run the built version
node dist/index.js

License

MIT