Split Panes

OpenCrabs supports tmux-style pane splitting in the TUI. Run multiple sessions side by side, each with its own provider, model, and context — all processing in parallel.

Splitting

How It Works

Each pane runs an independent session. You can have one pane writing code with Claude while another reviews tests with Gemini. The status bar shows [n/total] to indicate which pane is focused.

• Independent providers — Each pane can use a different AI provider and model
• Independent context — Conversation history is isolated per pane
• Parallel processing — All panes process concurrently via Tokio
• Persistent sessions — Each pane’s session is saved to SQLite like any other session

Example Layout

┌──────────────────────┬──────────────────────┐
│  Session 1 (Claude)  │  Session 2 (Gemini)  │
│  Writing code...     │  Reviewing PR...     │
├──────────────────────┴──────────────────────┤
│  Session 3 (OpenRouter)                      │
│  Running tests...                            │
└──────────────────────────────────────────────┘

Split vertically with _, then horizontally with | in the top pane.

Persistent Layout

Split pane configuration (splits, sizes, focused pane) saves to ~/.opencrabs/pane_layout.json on quit and Ctrl+C. On restart, your layout is restored exactly as you left it. Each restored pane preloads its session messages from the database, so content is visible immediately instead of blank.

Non-Focused Panes

Non-focused panes show compact tool call summaries and stripped reasoning text. Tool groups display as single collapsed lines matching the focused pane style. All panes auto-scroll to the bottom when new messages arrive.

v0.2.92 fixed several rendering issues:

• Tool calls no longer show a perpetual “running” spinner after completion
• Scroll position correctly tracks for inactive panes
• Stale cache is cleared when sessions are updated or deleted

State Management

Deleting a session now properly cleans up cached pane state. Previously, deleting a session left stale entries in the pane cache, which could cause phantom panes on restart.

Live Background Updates (v0.3.36)

Inactive panes now update live in the background. Previously, non-focused panes only refreshed when you switched focus to them. Now a background-session live-state cache routes IntermediateText and QueuedUserMessage events into per-session deltas, so you can watch tool calls and responses appearing in other panes in real time without switching focus.

Provider/model contamination prevention: When closing or switching panes, the old session’s provider is captured before the switch. This blocks cross-provider model leaks at 27 call sites throughout the codebase. The footer always shows the correct provider+model for the focused pane.

Ctrl+N binds the focused pane and live-refreshes the footer title, so new sessions show up immediately in the status bar.

Limits

There is no hard limit on pane count – you can run as many as your terminal fits. Each pane is a full session with its own token tracking and working directory.