Your first session

A first-session walkthrough: the window, the agent, the modes and the drawers, and the keys you use most. The keys below are the built-in defaults; see Keybindings for how to rebind them.

If Ship of Tools is not installed yet, start with the Quickstart.

The window

The window has three columns (two in the portrait preset, which drops the agent column). When the bottom drawer is open it sits under the navigation and preview columns; the agent column always runs the full height of the window.

The window with the Julia drawer open: navigation, preview and drawer on the left, the agent column full height on the right, the session strip along the bottom.

The left column is the navigation tree, a collapsible outline whose root you switch with one key. The middle column is the preview of whatever you have selected. The right column is the agent pane; its title bar reads llm. The focused pane's title bar instead shows the pane's name and its main keys, so with focus the agent pane's title reads Agent followed by its keys. The drawer shows the Julia REPL, a terminal, the host monitor or Help. Below the drawer, the row of names along the bottom edge is the session strip, one entry per session; the window's own bottom border reads fe <version> · be <version>, highlighted when they differ. See The interface.

Three plain lines sit around the navigation tree: status: above it shows the connection, the active workspace and a revision count; annotation: below it says whether the entry under the cursor has a concept annotation; key: at the bottom is the last key the window received.

On first launch the window opens in Files mode and the agent pane is empty: nothing runs there until you create a session.

The agent

1. Create a session. Press s for Sessions mode and pick [+ create new]; the keys are in Start an agent session.

2. Type a request. Move focus to the agent pane (Ctrl+Right, twice from the navigation pane) and type into it as you would into Claude Code or Codex in a terminal; it is the same program.

3. It runs code in your REPL. A Claude Code session runs Julia in the session's persistent REPL, the one Ctrl+J opens, and each of its runs appears in that drawer. See How agents use the REPL.

4. It shows you figures. A figure the agent produces is saved to a file, and the agent can put it in your preview pane with show-result; figures you produce yourself at the REPL prompt appear inline in the drawer.

5. Watch the row color. In Sessions mode the row color shows whether the agent is working, waiting for your answer or done; the colors are in Work-state colors.

The session keeps running when you switch rows. Closing the window ends it; see What keeps running.

Files mode — f

Press f for Files mode: filesystem navigation over the project. Move with the arrow keys — ↑ / ↓ to move through the tree, → to descend into a directory, ← to go back up. As you move, the preview pane renders the selected file: markdown rendered, images shown, .jl files syntax-highlighted, PDF pages rasterized, and a poster frame for video.

To edit a file yourself, move focus to the preview (Ctrl+Right) and press e: the file opens in the built-in editor in the preview pane. Ctrl+S saves; Escape closes it, and asks first if there are unsaved edits. When the entry has a concept annotation, e edits the annotation instead.

Files mode with src/DemoProject.jl selected; its source in the preview.

For what each file type renders and how, see Previews.

Modules mode — m

Press m for Modules mode: a structural view of the code, derived mechanically from JuliaSyntax.jl — modules and their definitions: types, functions, macros and submodules, with each type's constructors under it. It is read-only. Cursor position is preserved per mode, so switching f ↔ m returns you to where you were in each.

Modules mode: the cursor moves through a module's definitions, with docstring and source in the preview.

The full set of modes and their column shapes is in Modes.

The REPL drawer — Ctrl+J

Press Ctrl+J to open the REPL in the bottom drawer: a persistent Julia session that stays alive across drawer switches (and across window restarts when the backend outlives the window; see What keeps running). From Files mode you can run a whole .jl file in it without retyping — r runs it in a fresh REPL (this also clears what the agent built in Main), Shift+R includes it in the current one. At the prompt, type an expression and press Enter to run it (Shift+Enter inserts a newline); values, printed output, errors and images appear below it as they arrive.

The Julia drawer after running scripts/route.jl: the printed output and the figure inline.

For file dispatch and the display protocol, see The REPL.

The Terminal drawer — Ctrl+T

Press Ctrl+T for a local Terminal — an OS shell on the frontend machine, typically used to SSH out to backend hosts. The REPL and Terminal share one physical drawer slot: Ctrl+J and Ctrl+T each toggle their own pane, and pressing the other key swaps the content. See The interface.

The Monitor drawer — Ctrl+M

Press Ctrl+M for the Monitor drawer: CPU, memory and GPU history for your Linux hosts, read from /proc and nvidia-smi with no extra privileges (the sampler is a Linux script; a macOS host has no /proc to read). Which hosts it shows is configured in hosts.toml; see The Monitor drawer.

Navigation modes: Sessions — s — and Hosts — h

Two more nav-tree roots switch the target, not the content:

• s — Sessions. Every session on every connected host, and [+ create new] to start one (see The agent above). What a session is, and what it shares with other sessions, is in Sessions and persistence.

• h — Hosts. List every host the window dials, with its link state; Enter jumps to that host's sessions. See Hosts mode.

Help — Ctrl+? and F1

Press Ctrl+? for a five-second overlay of the focused pane's actions with their live bindings; press it again for the searchable Help drawer, or open the drawer directly with F1. Help lists the bindings in effect, including your rebinds.

The Help drawer (Ctrl+? twice): Tab widens the scope to all panes, typing zoom filters the actions, Down steps through them.

Layout and focus

A few global keys manage the window itself:

Action	Key	What it does
Move pane focus	Ctrl+Arrow	shift focus spatially between the panes
Next / previous session	Shift+Right / Shift+Left	make the next or previous session in the strip the active one
Maximize pane	Alt+=	fill the window with the focused pane
Wide-preview	Alt++	hide the agent pane and widen the preview pane
Restore layout	Esc	one layer per press: un-maximize first, then exit wide-preview (only while maximized or in wide-preview)
Font scale	Ctrl+= / Ctrl+-	zoom the UI font up / down (Ctrl+0 resets)
Reconnect	F5	reconnect the transport after a drop
Quit	Ctrl+Q	close the window, asking first; see What keeps running

Plain arrows move within a pane, Ctrl+Arrow moves between panes, and Shift+Right / Shift+Left switch sessions. The same chords are scoped so they do not conflict: in a text editor Shift with an arrow extends the selection, and in an image preview Shift+Up and Shift+Down zoom.

Where to go next

• Architecture — the three processes and why the language split.

• Modes and Previews — the nav surface in depth.

• The REPL and Running several agents — running code and driving agent sessions.

• Tutorial: an HDF5 preview and The dispatch ABI — add a preview for a new file type.