New "sherpa" wake_word provider: the configured phrase is BPE-tokenized at runtime against a small streaming zipformer KWS model (~13 MB English, one-time download cached under HERMES_HOME), so ANY typed phrase works with zero training — including per-profile phrases like "hey coder". wake.sherpa lazy-dep group + [wake] extra grow sherpa-onnx/sentencepiece; requirements probe routes per provider; sensitivity maps onto sherpa keywords_threshold. E2E-verified on real audio (target phrase fires, foreign phrase stays silent, reset drops buffered state).
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| sidebar_position | title | description |
|---|---|---|
| 11 | Wake Word | Hands-free 'Hey Hermes' wake word — start a voice session by speaking, the 'Hey Siri' way |
Wake Word ("Hey Hermes")
The wake word turns Hermes into a hands-free assistant across the CLI, TUI, and
desktop app: with one setting on, Hermes listens in the background for a spoken
trigger phrase. Say it, and Hermes starts a fresh session, opens the microphone,
captures your command via the normal voice pipeline,
and answers — exactly like "Hey Siri" or "Alexa". Use surface to pick which
one listens.
Detection runs entirely on-device. The always-on listener only watches for the wake phrase; no audio leaves your machine until you actually speak a command to the agent.
How it works
- With
wake_word.enabled: true(or after/wake on), a lightweight hotword detector listens on your default microphone. - When it hears the wake phrase it pauses itself (freeing the mic), starts a new session, and records one utterance with voice mode's silence detection.
- Your speech is transcribed and sent to the agent. After it replies, the listener resumes automatically and waits for the next wake word.
It is off by default — nothing listens until you turn it on.
Engines
| Engine | Cost | API key | Notes |
|---|---|---|---|
| openWakeWord (default) | Free | None | Local ONNX models. Ships a bundled "hey hermes" model (default); also supports hey_jarvis, alexa, hey_mycroft, … and custom models |
| sherpa | Free | None | Open vocabulary — detects ANY typed phrase with zero training. Small English model auto-downloads on first use (~13 MB) |
| Porcupine | Free tier / paid | PORCUPINE_ACCESS_KEY |
Picovoice engine; built-in keywords + custom .ppn files |
By default the phrase is "hey hermes" — a model for it ships with Hermes, so it works out of the box with no training. (On first use, openWakeWord downloads its shared feature-extraction models — a small one-time fetch.)
Both are lazy-installed the first time you enable the wake word. To install ahead of time:
cd ~/.hermes/hermes-agent && uv pip install -e ".[wake]"
Quick start
# In an interactive `hermes` session:
/wake on # start listening (installs the engine on first use)
/wake status # show phrase, provider, and state
/wake off # stop listening
Or enable it permanently in ~/.hermes/config.yaml:
wake_word:
enabled: true
Configuration
wake_word:
enabled: false
surface: auto # eligible surface: "auto" | "cli" | "tui" | "gui"
provider: openwakeword # "openwakeword" (free, local) | "porcupine"
phrase: "hey hermes" # cosmetic label only — detection is keyed by the model/keyword below
sensitivity: 0.5 # 0.0-1.0 — raise to reduce false triggers
start_new_session: true # start a fresh session on wake vs. continue the current one
openwakeword:
model: hey_hermes # bundled default; OR a built-in name OR a path to a custom .onnx/.tflite
inference_framework: onnx # "onnx" | "tflite"
porcupine:
keyword: jarvis # built-in keyword OR path to a custom .ppn
sensitivity, phrase, and start_new_session apply to both engines. The
openwakeword and porcupine blocks select the actual detection model.
Surfaces (CLI, TUI, GUI)
The wake word works in all three Hermes surfaces, and surface picks which one
owns the listener and opens the new session when it fires:
surface |
Behavior |
|---|---|
auto (default) |
All local surfaces are eligible; the first one to arm owns the listener. |
cli |
Only the classic hermes CLI. |
tui |
Only hermes --tui. |
gui |
Only the desktop app. |
The detector is on-device and single-mic, so only one surface listens at a time,
including when Hermes surfaces run in separate processes. Ownership is sticky:
the first eligible claimant keeps the listener until it stops, disconnects, or
its process exits. Hermes does not silently fail over to another open surface.
Set surface when you want to pin ownership instead of using first-claim wins.
The TUI and desktop GUI share the same Python backend (tui_gateway), which
runs the detector server-side and yields the mic to voice capture while a
command records.
Using a different phrase
"Hey Hermes" works out of the box — the bundled openWakeWord model
(model: hey_hermes) is the default. To wake on something else, the easiest
path is the open-vocabulary engine:
Option A — sherpa (any phrase, zero training)
Type the phrase you want; it's tokenized at runtime — "hey coder", "computer", "wake up neo", anything:
wake_word:
enabled: true
provider: sherpa
phrase: "hey coder" # detection key — just type your phrase
The small English KWS model (~13 MB) downloads once on first use. Each profile can set its own phrase — "hey <profile>" for every profile you run.
Option B — openWakeWord (free, trained model)
Name a built-in model (hey_jarvis, alexa, hey_mycroft, …), or train a
custom model (≈75–90 min on a free/Colab GPU) for maximum robustness, drop
the .onnx file somewhere, and reference it:
wake_word:
enabled: true
provider: openwakeword
phrase: "computer"
openwakeword:
model: ~/.hermes/wakewords/computer.onnx # or a built-in name like hey_jarvis
Training references:
:::tip Pick a distinctive phrase Wake phrases that don't collide with everyday speech generalize best. Two syllables with an uncommon word ("hermes" qualifies) beat common words like "hello" or "stop". :::
Option C — Porcupine (custom keyword in seconds)
Create a "Hey Hermes" keyword in the Picovoice Console,
download the .ppn, and:
wake_word:
enabled: true
provider: porcupine
phrase: "hey hermes"
porcupine:
keyword: ~/.hermes/wakewords/hey_hermes.ppn
Set your access key in ~/.hermes/.env:
PORCUPINE_ACCESS_KEY=your-key-here
Requirements
- A working microphone and the
sounddevice+numpyaudio stack (shared with voice mode). - An STT provider for transcribing the spoken command — local
faster-whisperworks out of the box; see Voice Mode for the full provider list. - The wake engine deps (auto-installed, or
hermes-agent[wake]).
/wake status reports exactly what's missing if the listener won't start.
Notes & limits
- Local surfaces only. The wake word runs in the CLI, TUI, and desktop GUI — wherever a local microphone is available. It does not run in the messaging gateway (Telegram, Discord, …), which has no mic.
- One mic at a time. The detector releases the microphone while a command is recording and reclaims it once the turn ends, so it won't fight voice capture.
- Privacy. Hotword detection is local. Set
sensitivityhigher if you get false triggers, lower if it misses you.