Echo

Patch a locally installed OpenClaw Control UI so that finishing an assistant reply plays a short Web-Audio two-tone "ding-dong" chime in the browser tab. Loc...

ClawHub package name: echo-cue (the slug echo is taken by another publisher; product is called echo locally).

Source: https://github.com/SymbolStar/echoCue

Click the floating 🔔 in the bottom-right corner to open the picker: enable / disable, choose a preset, Preview each sound — no DevTools required.

A zero-build local patch for OpenClaw Control UI (webchat) that plays a short two-tone chime (A5 → E5, ~900ms) when an assistant reply finishes streaming. Designed as a stop-gap until upstream PR openclaw/openclaw#73894 (issue #69186) lands.

Why this exists

OpenClaw Control UI has no completion sound on main yet. PR #73894 implements it but has been OPEN without review since 2026-04-29. This skill injects an equivalent IIFE into the bundled UI dist so it works today, and gracefully steps aside when upstream ships.

What you get

• Short ding-dong when the assistant finishes a reply
• Skipped for NO_REPLY / empty silent completions
• Always rings by default (foreground + background); set onlyHidden=on to limit to hidden tabs only
• 4-second hard rate-limit + content-fingerprint dedup → never double-rings on streaming re-renders
• Per-browser localStorage toggles (no UI surface added)
• One-shot apply / remove with backup
• Cache-bust: rewrites index.html to a new bundle filename so plain Cmd+R picks up the patch
• Patches every detected OpenClaw install (brew + nvm + OPENCLAW_HOME) so it works even when Gateway runs under a different node than which openclaw resolves
• Auto-detects upstream PR landing → skips itself

Install

bash apply.sh

Then refresh your Control UI browser tab (regular Cmd+R is enough, the script cache-busts the bundle filename). Click or press a key once on the page to unlock the AudioContext (this happens automatically the first time you send a message).

Verify

DevTools console:

window.__milly_cue_v1__   // → true

Send a question, switch to another tab — you should hear a ding-dong when the assistant finishes.

Toggle (per browser)

// Disable entirely
localStorage.setItem('milly.completionCue', 'off')

// Re-enable
localStorage.removeItem('milly.completionCue')

// Ring even when the tab is in foreground (default behaviour as of 0.2.0):
localStorage.removeItem('milly.completionCue.onlyHidden')

// Limit ringing to hidden / unfocused tabs only:
localStorage.setItem('milly.completionCue.onlyHidden', 'on')

Sound presets

Click the floating 🔔 button (bottom-right of Control UI) to open the picker: enable / disable, switch preset (with Preview button per row), toggle "Only when tab is hidden". Settings are stored in localStorage per browser.

key	group	description
chime (default)	Basic	Original two-tone bell (A5 → E5, ~900ms). 叮咚。
tritone	Basic	Approximation of the classic iPhone SMS "Tri-tone" — three quick bright pings (E6 / C6 / G6, ~420ms).
pop	Basic	Single bubble pop — quick upward swoop, ~110ms. 🫭
twinkle	Basic	Fast C → E → G arpeggio (triangle, ~280ms). ✨
droplet	Basic	Water droplet — downward sine sweep (1600 → 520 Hz, ~180ms). 💧
fishbite	Animal Crossing	Fish-bite plonk (low sine plop + tiny splash, ~220ms). 🐟
villager	Animal Crossing	Dialog "blip" — soft triangle chirp like villagers talking (~90ms). 🐾
acbell	Animal Crossing	Item ding — single bright bell tone with shimmer (~260ms). 🔔
coin	Super Mario	Classic two-note coin chirp (B5 → E6 square, ~220ms). 🪙
mariojump	Super Mario	Jump — fast upward square pitch sweep (~150ms). 🍄
oneup	Super Mario	1-Up fanfare — ascending arpeggio E5-G5-E6-C6-E6-G6 (~450ms). 🍄
powerup	Super Mario	Mushroom power-up — fast ascending climb (~360ms). 🌟
pipe	Super Mario	Warp pipe — descending square slide (~280ms). 🟢
bump	Super Mario	Block bonk — short low square thump with a click (~120ms). 🧱
nokia	Retro	Nokia tune — iconic 13-note phrase from Tárrega's Gran Vals (square, ~1.2s). 📱
modem	Retro	Dial-up modem mini-impression — hi/low tones + brief screech tail (~600ms). 📞

Add more presets by appending to the SOUNDS array in inject/completion-cue.iife.js (each entry needs key, label, play(ctx, master)), then re-run bash apply.sh. The widget picks them up automatically.

Hide the floating button

localStorage.setItem('milly.completionCue.widget', 'off')
localStorage.removeItem('milly.completionCue.widget')   // bring it back

DevTools fallback (still works):

__milly_cue_sounds__              // list available presets
__milly_cue_preview__('tritone')  // preview without sending a message
localStorage.setItem('milly.completionCue.sound', 'tritone')

Uninstall

bash remove.sh

Restores the original bundle from index-*.js.milly.bak and the original index.html from index.html.milly.bak.

After openclaw update

The update overwrites dist/control-ui/..., dropping the patch. Re-run:

bash apply.sh

apply.sh is idempotent and detects upstream:

• Already patched → skip
• Upstream responseCompletionSound shipped → skip + advise uninstall

Known limits

• Anchor: .chat-group.assistant DOM class. If OpenClaw renames it the patch silently does nothing (fail-quiet, no breakage).
• AudioContext requires one user gesture per page load (browser policy).
• Webchat only. TUI / iOS / macOS / Android clients are not covered (they have their own native notification stacks).
• Single audible cue per assistant turn regardless of message length.

File layout

File	Purpose
apply.sh	Detect every OpenClaw install, idempotent inject IIFE, backup, cache-bust
remove.sh	Restore from .milly.bak files
inject/completion-cue.iife.js	The patch payload
tests/manual.md	7-step verify checklist

Related

• Issue: openclaw/openclaw#69186
• Upstream PR (stop-gap target): openclaw/openclaw#73894
• Sibling skill (same pattern): agent-tab-title