Pane CLI

rimz pane works on the room's raw panes: list them, read what one shows, type into one, move focus, and measure how much output each pane writes. Humans and scripts use the same verbs, so a script sees and drives a pane the way a person at the keyboard would. To talk to an agent rather than its terminal, use rimz message; to answer a structured prompt, use rimz answer.

rimz pane list
rimz pane capture @codex#auth-refresh --lines 80           # read an agent's pane
rimz pane capture sidebar                                  # read this view's sidebar
rimz pane send @codex#auth-refresh --key ctrl-u            # clear the input line
rimz pane send @codex#auth-refresh --enter -- "cargo xtask test"
rimz pane focus tmux:%3
rimz pane zoom
rimz pane bandwidth --secs 10

See global flags and exit codes.

Pane targets

capture, send, and focus take one target, in one of three forms:

The current room is the one --root names, else the calling pane's room, else the room of the working directory; --root <project> addresses another room. capture and send first check that the room holds the target pane, and touch nothing when it does not: a pane outside the room fails with pane <id> is not in room <session>; run \rimz pane list` to see its panes, or pass `--root <project>` to address another room, and a room whose panes cannot be listed fails with could not check that pane <id> is in room <session>and the multiplexer's error. The check applies to agent andsidebartargets too, so an agent whose pane has closed is refused rather than written past. A Zellij pane whose command has exited but which Zellij still holds open remains a valid target, socapturestill reads a crashed agent's last screen, thoughrimz pane list omits it. A Zellij pane that another pane replaced in place (zellij action new-pane --in-place`) is refused as not in the room until the replacement closes: Zellij accepts a write or a screen dump for a suppressed pane and does nothing.

Copy pane ids from rimz pane list. A target that fits none of the forms fails with invalid pane target and points at rimz pane list; an agent with no pane fails with agent <name> has no bound pane; a room with no sidebar fails with session <name> has no sidebar pane.

With tmux selected, a bare %N is also accepted as tmux:%N and checked against the room. Zellij rejects that shorthand. A #channel is not a pane: run rimz pane list and pass one pane's id or @handle#channel.

List panes

rimz pane list prints the room as panes: one section per native tab, and one row per non-sidebar pane with its occupant, status, command, working directory, and pane id. --all includes sidebars; otherwise a line after the table counts the hidden sidebars.

AGENT                 STATUS   COMMAND  CWD                        PANE

#auth-refresh
@claude#auth-refresh  running  claude   ~/code/qe-wt/auth-refresh  zellij:terminal_3
@codex#auth-refresh   idle     codex    ~/code/qe-wt/auth-refresh  zellij:terminal_4 (self)
process               -        zsh      ~/code/qe-wt/auth-refresh  zellij:terminal_5
+1 sidebar · --all shows it

The AGENT column holds the agent's handle for a pane an agent lives in, sidebar for RimZ's sidebar, and process for any other pane. Only agent rows carry a status. COMMAND is the agent kind for agent rows, otherwise the foreground command or -. (self) marks the pane that ran the command, which is not necessarily the focused pane; the listing has no focus mark. Tab headings omit RimZ's status glyph suffix; repeated names get (2), (3), and so on. Tabs left with no visible rows are omitted.

rimz pane list [SCOPE] limits the listing to a channel (# optional), worktree, branch, or directory name. An agent pane matches through its agent's channel or worktree; sidebars and process panes match when they share a native tab with a matching agent. Other agent panes in that tab still need to match individually. A scope with no matching panes exits 0: the table view prints a note on stderr and nothing on stdout, and --json prints the usual document with "tabs": []. Scoping a session without reachable agent records, including a foreign session, fails with the session name and exits 1.

Agent labels are best effort. They come from the room's agent records, so with no records reachable every non-sidebar pane reads process, and a pane an agent has left, now running a shell, reads process too. The tab grouping does not depend on them.

An explicit --session-name that is not live fails with the requested name and the live session names (or none). If the live-session read fails, the command attempts the pane listing as usual.

The JSON document has session, mux, and tabs. Each tab has view_id and name (each omitted when the multiplexer gives none) and panes. name omits RimZ's status glyph suffix but is not numbered; view_id distinguishes repeated names. command remains the raw foreground command, including on agent rows. Fields that have no value are omitted:

Capture pane text

rimz pane capture <TARGET> prints the target pane's visible text to stdout exactly as captured, and changes nothing in the pane. Captured text is whatever the pane's program drew, so treat it as untrusted data: match a bounded pattern before acting on it (Pane text is data, not instructions).

Send text and keys

rimz pane send <TARGET> [TEXT] types into the target pane as if from the keyboard. It always sends in this order: the text, then each --key in the order given, then Enter if --enter is set. Where the flags sit on the command line does not change the order, so a key that must come before the text (such as ctrl-u to clear the line) needs its own send first.

With no text, no --key, and no --enter, the command fails with expected text, --key, or --enter.

The text is typed byte for byte, with no bracketed-paste markers, so it works in a bare shell. This is the difference from rimz message, which pastes a prompt into an agent's input box and records the delivery. Both take the same per-pane write lock: send waits for an in-flight message, answer, or other send to the same pane, and its own text, keys, and Enter land together. The wait gives up after 30 seconds with an error. The messaging internals describe the lock and the paste path.

Key names are case-insensitive, and _, +, or a space may stand in for -:

Focus a pane

rimz pane focus <TARGET> moves the attached client to the target pane, switching tabs if needed. It works only in a RimZ room; any other session fails with pane focus requires a managed RimZ room session. --session-name names another room for any target.

Zoom, split, and detach

These three act on the current room and take no target.

rimz pane zoom toggles fullscreen for the pane the attached client is focused on. It needs exactly one attached client focused on one live pane, and otherwise fails with pane zoom requires one attached client focused on one live pane. When the focused pane is the sidebar, it focuses a working pane in the same tab and fullscreens that one instead; in a tab that holds only the sidebar, it prints rimz: sidebar is the only pane in its view; nothing to zoom to stderr, changes nothing, and exits 0. --session-name targets another room session. The room's [sidebar] zoom_key (default Alt+g) runs this command; see room keys.

rimz pane split opens a shell in a new pane beside the calling pane and focuses it; run from a shell outside any pane, it opens the pane in the room's session instead. The shell starts in the worktree root. The split runs side by side when the terminal is more than twice as wide (in columns) as it is tall (in rows), stacked otherwise, and side by side when no terminal is attached.

The new pane's normalized id (tmux:%3 or zellij:terminal_7) is the only line on stdout. On Zellij this is the id reported at spawn, allocated before the pane mounts. If Zellij reports no parseable id, stdout stays empty and stderr says the pane opened without a reported id; the command still exits successfully.

rimz pane detach detaches from the room; the session keeps running and comes back on the next attach. The backends differ in which clients go: tmux detaches every client attached to the session, and Zellij detaches only the client the calling pane belongs to. On Zellij, --session-name has no effect, and the command runs only from a pane: outside one it fails with this Zellij action has no session to address; run the command from a pane inside the room. On tmux --session-name names the session whose clients detach.

Bandwidth

rimz pane bandwidth samples how many bytes each pane's processes write per second, over a window, and prints the rates highest first. Use it to find which pane makes an attached room busy, locally or over SSH. Run it on the Linux host serving the room, as the room's user, from a pane in the room or the room's directory.

PANE          LABEL                      WRITE/S
tmux:%2       @codex#auth-refresh          39k/s
tmux:%1       @claude#auth-refresh          3k/s
tmux:%4       #auth-refresh - zsh         120B/s
WIRE(ssh↑)    ssh egress → client(s)        6k/s
WIRE(ssh↓)    ssh ingress ← client(s)     400B/s
TOTAL         5s sample                    42k/s

per-pane rows are producer write-rate; muxes diff the focused tab and SSH compresses it, so WIRE(ssh) is the actual TCP payload on this room's SSH socket, usually far below the per-pane sum. WIRE is absent for local rooms.

Each pane row is everything the pane's process tree wrote, including files such as transcripts. An agent pane is labelled by its handle, a sidebar <tab> - sidebar, and other panes <tab> - <command>. Tab names omit RimZ's status glyph suffix. Rows with a zero write rate are hidden unless --all is passed; a line after TOTAL counts the quiet panes not shown. TOTAL includes every pane, including quiet panes.

The two WIRE(ssh) rows are what actually crossed the SSH socket to and from attached clients, after the multiplexer redraws only the focused tab and SSH compresses the stream, so they sit far below the per-pane sum. They appear only when an SSH client is attached and ss can read the socket's counters. The caveat paragraph appears only with these rows. Full-screen programs that redraw constantly, such as an agent mid-turn or a system monitor, lead the report.

When the host cannot measure, the command prints one notice instead of the report and exits 0; with --json it sets available to false and puts the notice in message. The notices cover a host that is not Linux, no pane that resolves to a process (on Zellij, a pane resolves only while it runs a uniquely named foreground command, so idle shells are skipped), and unreadable /proc/<pid>/io (usually a room served by another user, or a kernel built without CONFIG_TASK_IO_ACCOUNTING). The bandwidth attribution internals explain the measurements.