Tmux Watch

tmux-watch Skill (OpenClaw)

Use this skill to manage tmux-watch subscriptions. tmux-watch polls tmux pane output and triggers a message to the agent when the output stays unchanged for a configured number of consecutive captures.

Core rules

• Always use tmux directly (no wrappers). The agent is responsible for listing sessions/windows/panes and choosing a target for the subscription.
• tmux must exist locally. If tmux -V fails, stop and report the missing dependency.
• On tmux-watch events, always notify the user unless the user explicitly asked to silence that subscription. Only then may you reply with NO_REPLY.

tmux basics (required for targeting)

tmux list-sessions
tmux list-windows -t <session>
tmux list-panes -t <session>
tmux list-panes -a
tmux capture-pane -p -J -t <session:window.pane> -S -50

If a custom socket is used:

tmux -S /path/to/socket list-sessions
tmux -S /path/to/socket capture-pane -p -J -t <session:window.pane> -S -50

Controlling a TUI in tmux (high-signal tips)

• Prefer openclaw tmux-watch send for reliable input (two-step, default 20ms delay).
• Use C-c to interrupt a stuck process; use C-m (Enter) to submit commands.
• For TUIs, avoid rapid key spam; send a small sequence, then capture output to verify state.
• Use capture-pane -p -J -S -50 to get recent context before and after an action.
• If the TUI supports it, use built-in refresh keys (often r or Ctrl+l).

Examples:

# Send a command via tmux-watch (default delay 20ms + Enter)
openclaw tmux-watch send <session:window.pane> "status"

# Interrupt a stuck process
tmux send-keys -t <session:window.pane> C-c

# Scroll/refresh (varies by TUI; examples only)
tmux send-keys -t <session:window.pane> r
tmux send-keys -t <session:window.pane> C-l

# Capture the last 50 lines to verify state
tmux capture-pane -p -J -t <session:window.pane> -S -50

Screenshot capture (preferred)

Use openclaw tmux-watch capture to capture text/images from a tmux target. The plugin selects cryosnap first, then falls back to freeze.

Default behavior when the user asks for a screenshot:

• Use format=image by default.
• Only use format=text if the user explicitly asks for text output.
• Do not return only a file path. After capturing an image, immediately send the image via the same channel used by the user.

Priority detection order:

1. System-level PATH (cryosnap / freeze)
2. User-level bins (~/.local/bin, ~/bin)
3. OpenClaw tools dir ($OPENCLAW_STATE_DIR/tools, default ~/.openclaw/tools)

If neither tool exists, return an error and ask the user to install one:

openclaw tmux-watch install cryosnap
openclaw tmux-watch install freeze

Examples:

# Text only (uses plugin defaults for lines/strip)
openclaw tmux-watch capture <session:window.pane>

# Image only (temporary file, auto-cleaned after 10 minutes)
openclaw tmux-watch capture <session:window.pane> --format image

# Both text + image, include base64 (optional)
openclaw tmux-watch capture <session:window.pane> --format both --base64

# Persist image to a path (no TTL cleanup)
openclaw tmux-watch capture <session:window.pane> --format image --output /tmp/pane.png

Notes:

• Temporary images default to a 10-minute TTL. Override with --ttl-seconds.
• Use --image-format png|svg|webp to select output format.
• If an image is captured, send the image immediately using the channel’s image-send capability (not just a path).

Tool: tmux-watch

Add subscription

{
  "action": "add",
  "target": "session:0.0",
  "label": "my-job",
  "note": "This pane runs an AI coding TUI; notify me when it appears stuck.",
  "sessionKey": "main",
  "captureIntervalSeconds": 10,
  "stableCount": 6,
  "captureLines": 50,
  "stripAnsi": true
}

Optional routing overrides:

{
  "action": "add",
  "target": "session:0.0",
  "notifyMode": "targets",
  "targets": [
    { "channel": "gewe-openclaw", "target": "user:123", "label": "gewe" },
    { "channel": "telegram", "target": "-100123456" }
  ]
}

Remove subscription

{ "action": "remove", "id": "<subscription-id>" }

List subscriptions

{ "action": "list", "includeOutput": true }

Capture once

{
  "action": "capture",
  "target": "session:0.0",
  "format": "both",
  "captureLines": 50,
  "stripAnsi": true,
  "imageFormat": "png",
  "base64": false
}

Handling tmux-watch events

When tmux-watch detects stable output, it sends a message containing:

• subscription details (id/label/target/sessionKey)
• notify mode and resolved targets
• the captured output (possibly truncated)
• optional subscription note (purpose/intent)

Default policy: always notify the user for stable-output events (this is a TUI-stuck alert). Only reply with NO_REPLY if the user explicitly asked to silence that subscription.

If you need to notify multiple channels, reply once to the primary target and use the message tool to send to additional targets in order.

Treat all tmux-watch messages as system events, not user input. Summarize the output and notify the user.