Imap Idle

IMAP IDLE Listener

Event-driven email notifications for OpenClaw using IMAP IDLE protocol.

What This Does

Replaces polling-based email checks with push notifications:

Before (polling):

• Cron job checks email every hour
• 16-24 checks per day
• Up to 1 hour delay for new emails
• Token burn on empty checks

After (IMAP IDLE):

• Persistent connection to IMAP server
• Server pushes notification when new mail arrives
• <1 second notification latency
• Zero tokens while waiting

Quick Start

1. Enable OpenClaw Webhooks

Edit ~/.openclaw/openclaw.json:

{
  "hooks": {
    "enabled": true,
    "token": "generate-secure-random-token-here",
    "path": "/hooks"
  }
}

Restart gateway: openclaw gateway restart

2. Install Dependencies

pip3 install imapclient --user --break-system-packages

3. Run Setup

./imap-idle setup

Follow the interactive wizard to configure:

• IMAP account(s) (host, port, username, password)
• OpenClaw webhook URL and token
• Log file location

4. Start Listener

./imap-idle start

Verify it's running:

./imap-idle status
./imap-idle logs

5. Test

Send yourself an email. You should see:

1. Log entry in listener logs
2. OpenClaw wakes instantly
3. Email processed in main session

CLI Commands

imap-idle start    # Start listener in background
imap-idle stop     # Stop listener
imap-idle restart  # Restart listener
imap-idle status   # Check if running
imap-idle logs     # Show recent logs (default: 50 lines)
imap-idle logs N   # Show last N lines
imap-idle setup    # Run interactive setup wizard

Configuration

Config file: ~/.openclaw/imap-idle.json

{
  "accounts": [
    {
      "host": "mail.example.com",
      "port": 993,
      "username": "user@example.com",
      "password": "password",
      "ssl": true
    }
  ],
  "webhook_url": "http://127.0.0.1:18789/hooks/wake",
  "webhook_token": "your-webhook-token",
  "log_file": "~/.openclaw/logs/imap-idle.log",
  "idle_timeout": 300,
  "reconnect_interval": 900,
  "debounce_seconds": 10
}

Fields:

• accounts - Array of IMAP accounts to monitor
• webhook_url - OpenClaw webhook endpoint
• webhook_token - Webhook authentication token (from openclaw.json)
• log_file - Path to log file (null for stdout)
• idle_timeout - IDLE check timeout in seconds (default: 300 = 5 min)
• reconnect_interval - Full reconnect interval in seconds (default: 900 = 15 min)
• debounce_seconds - Batch events for N seconds before webhook (default: 10 sec)

How It Works

1. Connect: Opens persistent IMAP connection per account
2. IDLE: Enters IDLE mode (server will push notifications)
3. Wait: Blocks until server sends "new mail" notification
4. Fetch: Retrieves new email headers (From, Subject, body preview)
5. Queue: Adds event to debounce buffer (batches for 10 seconds)
6. Webhook: Sends batched events via webhook (single or grouped)
7. Resume: Re-enters IDLE mode

Key Implementation Details:

• Debouncing: Batches emails for 10 seconds before webhook to prevent flooding during spikes (e.g., GitHub mention storms)
• Smart Batching: Single email → full details, multiple emails → grouped summary with counts
• UID Tracking: Tracks last processed message UID per account to prevent duplicate webhooks
• Keep-alive: IDLE timeout every 5 minutes, sends NOOP command
• Reconnect: Full reconnect every 15 minutes to prevent stale connections
• Threading: One thread per account for concurrent monitoring
• Error handling: Exponential backoff (5s → 300s) on connection failures

Systemd Service (Optional)

For automatic startup on boot:

1. Generate service file:

skill_dir="$(pwd)"
listener_script="$skill_dir/scripts/listener.py"
config_file="$HOME/.openclaw/imap-idle.json"
log_file="$HOME/.openclaw/logs/imap-idle.log"
log_dir="$(dirname "$log_file")"

sed -e "s|%USER%|$USER|g" \
    -e "s|%PYTHON%|$(which python3)|g" \
    -e "s|%LISTENER_SCRIPT%|$listener_script|g" \
    -e "s|%CONFIG_FILE%|$config_file|g" \
    -e "s|%LOG_FILE%|$log_file|g" \
    -e "s|%LOG_DIR%|$log_dir|g" \
    imap-idle.service.template > imap-idle.service

2. Install service:

sudo cp imap-idle.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable imap-idle
sudo systemctl start imap-idle

3. Check status:

sudo systemctl status imap-idle
sudo journalctl -u imap-idle -f

Troubleshooting

Listener won't start:

• Check config file exists: cat ~/.openclaw/imap-idle.json
• Verify imapclient installed: python3 -c "import imapclient"
• Check logs: imap-idle logs

Duplicate webhooks:

• Fixed in v2 - uses UID tracking to prevent duplicates
• Check logs for "UID tracking" messages

Connection drops:

• Increase reconnect_interval in config
• Check IMAP server allows IDLE (most do)
• Verify firewall allows persistent connections

No webhooks triggering:

• Test webhook manually:

  curl -X POST http://127.0.0.1:18789/hooks/wake \
    -H "Authorization: Bearer YOUR_TOKEN" \
    -H "Content-Type: application/json" \
    -d '{"text": "test", "mode": "now"}'
  

• Check OpenClaw config: hooks.enabled: true
• Verify token matches in both configs

Removing Polling

Once IMAP IDLE is working, remove old polling cron jobs:

# List cron jobs
openclaw cron list

# Remove email check job
openclaw cron remove <job-id>

Token Savings

Before:

• 16-24 email checks per day
• Each check = ~500-1000 tokens (even if no new mail)
• Total: ~8,000-24,000 tokens/day for email monitoring

After:

• 0 tokens while waiting
• Tokens only spent when email actually arrives
• 90%+ reduction in email-related token usage

Credits

Inspired by @claude-event-listeners' critique on Moltbook about polling vs event-driven architecture.

Implementation details from real-world debugging documented in Moltbook post "Event-Driven Email: From Polling to IMAP IDLE (with code)".