Monitor tmux panes running Claude processes for inactivity with notifications

monitor_tmux_pane.sh

#!/bin/zsh

# Usage: ./monitor_tmux_pane.sh [idle_threshold_seconds]
# Monitors all tmux panes running Claude processes

IDLE_THRESHOLD="${1:-5}"  # seconds, default 5
DEBOUNCE_TIME=30  # seconds before we can send another notification

# Trap Ctrl+C to exit cleanly
trap 'echo -e "\nMonitoring stopped."; exit 0' INT

# Get all tmux panes that contain Claude processes
get_claude_panes() {
    # Get all Claude PIDs
    local claude_pids=($(ps -eo pid,comm | awk '$2 == "claude" {print $1}'))
    
    if [ ${#claude_pids[@]} -eq 0 ]; then
        return
    fi
    
    # For each Claude PID, find which tmux pane it belongs to
    for claude_pid in "${claude_pids[@]}"; do
        # Get the terminal of the Claude process
        local tty=$(ps -p "$claude_pid" -o tty= 2>/dev/null | sed 's/^[[:space:]]*//; s/[[:space:]]*$//')
        
        if [[ -n "$tty" && "$tty" != "??" ]]; then
            # Find tmux pane with matching tty
            tmux list-panes -a -F '#{session_name}:#{window_index}.#{pane_index}|#{pane_tty}' | while IFS='|' read pane_id pane_tty; do
                # Compare just the tty name (e.g., ttys003)
                if [[ "/dev/$tty" == "$pane_tty" ]]; then
                    echo "$pane_id"
                fi
            done
        fi
    done | sort -u
}

CLAUDE_PANES=($(get_claude_panes))

if [ ${#CLAUDE_PANES[@]} -eq 0 ]; then
    echo "No tmux panes running Claude found"
    exit 1
fi

echo "Found Claude panes: ${CLAUDE_PANES[*]}"
echo "Monitoring for inactivity (threshold: ${IDLE_THRESHOLD}s, debounce: ${DEBOUNCE_TIME}s)"
echo "Press Ctrl+C to stop monitoring"

# Reload tmux config to ensure activity monitoring is enabled
tmux source-file ~/.tmux.conf >/dev/null 2>&1

# Associative arrays to track state for each pane
typeset -A LAST_ACTIVITY
typeset -A LAST_NOTIFICATION
typeset -A NOTIFICATION_SENT

# Get a hash of the pane's visible content
get_pane_content_hash() {
    tmux capture-pane -t "$1" -p 2>/dev/null | md5
}

# Associative array to track content hash
typeset -A LAST_CONTENT_HASH
typeset -A LAST_ACTIVITY_TIME

# Initialize state for each pane
for pane in "${CLAUDE_PANES[@]}"; do
    LAST_CONTENT_HASH[$pane]=$(get_pane_content_hash "$pane")
    LAST_ACTIVITY_TIME[$pane]=$(date +%s)
    LAST_NOTIFICATION[$pane]=0
    NOTIFICATION_SENT[$pane]=false
done

while true; do
    # Refresh Claude panes list (in case new ones start or old ones stop)
    CURRENT_PANES=($(get_claude_panes))
    
    # Add new panes to our tracking
    for pane in "${CURRENT_PANES[@]}"; do
        if [[ -z "${LAST_CONTENT_HASH[$pane]}" ]]; then
            echo "$(date '+%Y-%m-%d %H:%M:%S') - New Claude pane detected: $pane"
            LAST_CONTENT_HASH[$pane]=$(get_pane_content_hash "$pane")
            LAST_ACTIVITY_TIME[$pane]=$(date +%s)
            LAST_NOTIFICATION[$pane]=0
            NOTIFICATION_SENT[$pane]=false
        fi
    done
    
    # Monitor each Claude pane
    for pane in "${CURRENT_PANES[@]}"; do
        # Check if pane still exists
        if ! tmux list-panes -t "$pane" >/dev/null 2>&1; then
            # Only report termination if we were tracking this pane
            if [[ -n "${LAST_CONTENT_HASH[$pane]}" ]]; then
                echo "$(date '+%Y-%m-%d %H:%M:%S') - Pane '$pane' no longer exists"
            fi
            unset LAST_CONTENT_HASH[$pane]
            unset LAST_ACTIVITY_TIME[$pane]
            unset LAST_NOTIFICATION[$pane]
            unset NOTIFICATION_SENT[$pane]
            continue
        fi
        
        CURRENT_CONTENT_HASH=$(get_pane_content_hash "$pane")
        CURRENT_TIME=$(date +%s)
        
        # Check if pane content changed
        if [ "$CURRENT_CONTENT_HASH" != "${LAST_CONTENT_HASH[$pane]}" ]; then
            LAST_CONTENT_HASH[$pane]="$CURRENT_CONTENT_HASH"
            LAST_ACTIVITY_TIME[$pane]=$CURRENT_TIME
            NOTIFICATION_SENT[$pane]=false  # Reset notification flag when activity resumes
            echo "$(date '+%Y-%m-%d %H:%M:%S') - Pane '$pane': activity detected"
        else
            # Calculate idle duration based on last activity time
            IDLE_DURATION=$((CURRENT_TIME - ${LAST_ACTIVITY_TIME[$pane]}))
            
            if [ $IDLE_DURATION -ge $IDLE_THRESHOLD ]; then
                # Check if we should send a notification
                TIME_SINCE_LAST_NOTIFICATION=$((CURRENT_TIME - ${LAST_NOTIFICATION[$pane]}))
                
                if [ "${NOTIFICATION_SENT[$pane]}" = false ]; then
                    if [ $TIME_SINCE_LAST_NOTIFICATION -ge $DEBOUNCE_TIME ]; then
                        echo "$(date '+%Y-%m-%d %H:%M:%S') - ALERT: Pane '$pane' idle for ${IDLE_DURATION}s"
                        printf '\ePtmux;\e\e]9;Claude pane %s idle for %d seconds\a\e\\' "$pane" "$IDLE_DURATION"
                        LAST_NOTIFICATION[$pane]=$CURRENT_TIME
                        NOTIFICATION_SENT[$pane]=true
                    else
                        echo "$(date '+%Y-%m-%d %H:%M:%S') - Pane '$pane' idle for ${IDLE_DURATION}s (notification suppressed, ${TIME_SINCE_LAST_NOTIFICATION}s since last)"
                        NOTIFICATION_SENT[$pane]=true
                    fi
                fi
            else
                echo "$(date '+%Y-%m-%d %H:%M:%S') - Pane '$pane' idle for ${IDLE_DURATION}s (threshold: ${IDLE_THRESHOLD}s)"
            fi
        fi
    done
    
    sleep 1
done

Claude Tmux Activity Monitor

This script monitors all tmux panes running Claude processes and sends OS notifications when they become idle.

Features

• Auto-discovery: Automatically finds all tmux panes running Claude processes
• Real-time monitoring: Detects activity by monitoring pane content changes
• Smart notifications: Sends OS notifications when panes go idle for 5+ seconds
• Debounce protection: 30-second cooldown prevents notification spam
• Dynamic tracking: Automatically handles new/terminated Claude processes
• Per-pane state: Each pane tracked independently with its own idle timer

Usage

# Monitor all Claude panes with 5-second idle threshold (default)
./monitor_tmux_pane.sh

# Monitor with custom idle threshold (10 seconds)
./monitor_tmux_pane.sh 10

Requirements

• tmux with activity monitoring enabled (monitor-activity on in .tmux.conf)
• zsh shell
• Claude processes running in tmux panes

How it works

1. Finds all Claude process PIDs using ps
2. Maps PIDs to tmux panes by matching TTY devices
3. Monitors pane content changes using MD5 hashes
4. Sends macOS notifications via tmux escape sequences when idle threshold is reached
5. Resets idle timer when activity resumes

Perfect for getting notified when your Claude conversations go quiet!