VoiceLayer

Your AI agent can’t hear you and respond to you. VoiceLayer gives it ears and a voice.

Voice I/O for AI coding assistants. Press F5, speak to Claude Code, get on-device transcription in under 1.5 seconds. Your AI speaks back. Works with any MCP client.

On a mouse with side buttons, button 5 (forward) works like F5 and button 4 (back) presses Return.

Select text in any app and press Option+F5 to read it aloud; press it again to stop. Shift+F5 re-pastes the last transcript. Option+F5 is ignored during dictation or transcription. Secure fields are never read. If a safe clipboard backup is unavailable, the shortcut asks you to retry and leaves the clipboard intact.

  You ──🎤──> whisper.cpp ──> Claude Code ──> edge-tts ──🔊──> You
         STT (local)           MCP tools         TTS (free)

Local-first. Free. Open-source. No cloud APIs, no API keys, no data leaves your machine.

Website · Docs · npm

Install

macOS (recommended) — the tap ships the CLI/MCP package and the notarized notch app:

brew tap etanhey/layers
brew install etanhey/layers/voicelayer         # CLI + MCP server
brew install --cask etanhey/layers/voicebar    # VoiceBar notch app (owns the mic)
voicelayer setup                               # one-time runtime setup

Install the cask too — the formula alone gives you the CLI/MCP but no notch UI.

npm — if you only want the MCP server:

bun add -g voicelayer-mcp        # or: npm i -g voicelayer-mcp
brew install sox socat && pip3 install edge-tts
brew install whisper-cpp         # optional, for local STT

# whisper model (~1.5 GB) — needed for local STT
mkdir -p ~/.cache/whisper && curl -L -o ~/.cache/whisper/ggml-large-v3-turbo.bin \
  https://huggingface.co/ggerganov/whisper.cpp/resolve/main/ggml-large-v3-turbo.bin

Speak from the terminal

voicelayer speak "Hello"
echo "Text to read" | voicelayer speak
voicelayer speak - --markdown
voicelayer speak --file notes.md --profile long --wait
voicelayer speak --stop

Speech goes through the running VoiceLayer daemon, sharing Stop and the teleprompter. With the daemon, the command returns after the first audio starts; --wait waits for completion. --profile auto is the default; short and long select the corresponding profile. Auto selects the saved long profile above short_limit_chars and the short profile at or below the threshold (default: 400 characters). --profile short|long overrides that choice. Markdown conversion defaults on for .md files; literal text and stdin are plain unless --markdown is supplied. Long reads stream chunks without the MCP tool’s text cap, up to the shared 200,000-character safety limit.

If the daemon is unavailable, the CLI reports it on stderr and runs the same streaming engine in the foreground, waiting for completion even without --wait. Ctrl-C stops local synthesis/playback and waits for owned children to exit. Local fallback has no teleprompter; --stop requires the daemon. Authentication, busy, synthesis and playback failures return a nonzero exit code. Failures after an async daemon command has returned are reported by the daemon; use --wait when the final exit status matters. An older running daemon must be updated/restarted to support this command.

Speech credentials resolve in this order: VOICELAYER_DAEMON_SECRET_PATH, isolated VOICELAYER_STATE_DIR, an MCP socket override, VOICELAYER_TTS_DAEMON_SECRET_FILE, VOICELAYER_TTS_AUTH_TOKEN_FILE, then ~/.voicelayer/daemon.secret. Isolation paths take precedence over inherited TTS aliases. Secret files must be regular, nonempty, non-symlink files with mode 0600.

Point your MCP client at the daemon

VoiceLayer runs as one persistent daemon on a Unix socket; every session connects through a lightweight socat shim instead of spawning its own process. Add to .mcp.json:

{
  "mcpServers": {
    "voicelayer": {
      "command": "socat",
      "args": ["STDIO", "UNIX-CONNECT:/tmp/voicelayer-mcp.sock"]
    }
  }
}

Or migrate every repo at once: bash scripts/migrate-to-daemon.sh (--dry-run to preview). On macOS, grant your terminal microphone access (System Settings → Privacy → Microphone).

Updates, kill-switches, and cross-machine setup: docs/install-and-update.md.

The two tools

Both ship full MCP ToolAnnotations. Neither is destructive; both set openWorldHint: false.

Daemon speech profiles, env overrides, and socket controls: docs/tts-settings.md.

How voice_ask works: waits for any playing audio to finish → speaks the question via edge-tts → records the mic and resamples to 16kHz → Silero VAD detects when you stop talking → whisper.cpp transcribes locally (~200-400ms on Apple Silicon) → returns the text to your agent.

Full tool parameters: docs/tools-reference.md.

VoiceBar — the notch surface (macOS)

The canonical UI (SwiftUI + AppKit). It tucks around the MacBook camera housing instead of floating over your work:

• Liquid-Glass wings flank the camera housing, with a graceful fallback on older macOS.
• Teleprompter with word-by-word karaoke highlighting as your agent speaks.
• Idle-hover to summon — collapsed it draws no pixels; hovering reveals the mic, History and Settings.
• Settings — General · Models · Dictionary · History. Open with ⌘, or right-click → Settings…, or from a script: open voicebar://settings/models.
• Morph animations between idle ↔ recording ↔ speaking, Reduce-Motion aware.

STT backends

Auto-detected. Override with QA_VOICE_STT_BACKEND=whisper|wispr|auto.

Platform support

Part of Golems

Pair with BrainLayer to remember voice conversations across sessions.

More

• Architecture — why one daemon instead of a process per session
• Configuration — environment variables and test commands
• Contributing

License

Apache-2.0