tmux

tmux Skill

Use tmux as a programmable terminal multiplexer for interactive work. Works on Linux and macOS with stock tmux; avoid custom config by using a private socket.

Quickstart (use current tmux server)

SESSION=python-debug                           # descriptive names; avoid spaces
tmux new -d -s "$SESSION"
tmux send-keys -t "$SESSION".1 -- 'python3 -q' Enter
tmux capture-pane -p -J -t "$SESSION".1 -S -200  # watch output
tmux kill-session -t "$SESSION"                # clean up

If not running inside tmux (no $TMUX env var), use an isolated socket:

SOCKET_DIR=${TMPDIR:-/tmp}/claude-tmux-sockets
mkdir -p "$SOCKET_DIR"
SOCKET="$SOCKET_DIR/claude.sock"
SESSION=python-debug
tmux -S "$SOCKET" new -d -s "$SESSION"
tmux -S "$SOCKET" send-keys -t "$SESSION".1 -- 'python3 -q' Enter
tmux -S "$SOCKET" capture-pane -p -J -t "$SESSION".1 -S -200
tmux -S "$SOCKET" kill-session -t "$SESSION"

After starting a session ALWAYS tell the user how to monitor the session by giving them a command to copy paste:

To monitor this session yourself:
  tmux attach -t python-debug

Or to capture the output once:
  tmux capture-pane -p -J -t python-debug.1 -S -200

If using an isolated socket (not in tmux), include -S "$SOCKET":

To monitor this session yourself:
  tmux -S "$SOCKET" attach -t python-debug

Or to capture the output once:
  tmux -S "$SOCKET" capture-pane -p -J -t python-debug.1 -S -200

This must ALWAYS be printed right after a session was started and once again at the end of the tool loop. But the earlier you send it, the happier the user will be.

Socket convention

• Preferred: When running inside tmux (check $TMUX env var), use the current tmux server without -S flag.
• Fallback: If not in tmux, agents MUST place tmux sockets under CLAUDE_TMUX_SOCKET_DIR (defaults to ${TMPDIR:-/tmp}/claude-tmux-sockets) and use tmux -S "$SOCKET" so we can enumerate/clean them. Create the dir first: mkdir -p "$CLAUDE_TMUX_SOCKET_DIR".
• Default socket path to use unless you must isolate further: SOCKET="$CLAUDE_TMUX_SOCKET_DIR/claude.sock".