kesha-voice-kit

---
name: kesha-voice-kit
description: Local multilingual voice toolkit — speech-to-text (STT), text-to-speech (TTS), speaker diarization, and language detection, over a CLI or an MCP server. Runs entirely offline on Apple Silicon, Linux, and Windows. No API keys, no cloud. NVIDIA Parakeet TDT for STT across 25 European languages, Kokoro-82M + Vosk-TTS for TTS in 9 languages, plus macOS AVSpeechSynthesizer for ~180 system voices with zero install.
emoji: 🎙️

requires:
  bins: [kesha]

install:
  - kind: bash
    cmd: bun add -g "@drakulavich/kesha-voice-kit"
  - kind: bash
    cmd: kesha install
---

# kesha-voice-kit

Local voice toolkit: transcribe voice messages to text, synthesize speech, detect language of audio or text. Fully offline after `kesha install`. No API keys, no per-minute billing.

**Trigger keywords for when to use this skill:** voice message, voice memo, voice note, .ogg, .opus, .wav, .mp3, audio file, transcribe, transcription, speech-to-text, STT, text-to-speech, TTS, synthesize speech, say, telegram voice note, whatsapp voice note, ogg-opus, opus, multilingual voice, multilingual ASR, language detection, speaker diarization, who said what, meeting transcript, MCP server, offline voice, privacy, Apple Silicon, CoreML.

## When to use

- **Voice memo arrived** (Telegram, WhatsApp, Slack, Signal .ogg/.opus/.m4a): transcribe with `kesha --json <path>` and branch on the detected language.
- **Need to send a voice note (Telegram, WhatsApp, Signal, Discord)**: synthesize directly into messenger-native OGG/Opus with `kesha say --format ogg-opus --out reply.ogg "<text>"`. Default is mono 24 kHz @ 32 kbps - what Telegram `sendVoice` expects. No WAV redirect and no `ffmpeg` round-trip.
- **Need local file playback/debug output**: WAV is still available with `kesha say --out reply.wav "<text>"`, but do not use WAV for Telegram voice replies. Auto-routes by detected language (Kokoro-82M for English, Vosk-TTS for Russian). On darwin-arm64, English Kokoro uses FluidAudio CoreML instead of ONNX. For other languages and ~180 more voices use `--voice macos-*` on macOS (zero model download).
- **Need to detect what language a file is in** before choosing a pipeline: `kesha --json audio.ogg` returns both audio-based and text-based language detection with confidence scores.
- **Need to capture your own voice** for transcription or as a voice-note source: `kesha record --out clip.wav` records up to 120s (override with `--max-seconds`) of mono 16 kHz WAV from the default microphone. Pipe straight into `kesha --json clip.wav` to close the loop.

## OpenClaw plugin setup

Install the plugin, then explicitly route OpenClaw audio understanding through the CLI model entry. The plugin registration makes Kesha discoverable, but real voice-message transcription uses `tools.media.audio.models` with a `type: "cli"` entry.

```bash
bun add -g @drakulavich/kesha-voice-kit
kesha install
openclaw plugins install @drakulavich/kesha-voice-kit
openclaw config patch --stdin <<'JSON5'
{
  tools: {
    media: {
      audio: {
        enabled: true,
        models: [
          {
            type: "cli",
            command: "kesha",
            args: ["{{MediaPath}}"],
            timeoutSeconds: 15,
          },
        ],
        echoTranscript: true,
        echoFormat: '🦜 "{transcript}"',
      },
    },
  },
}
JSON5
```

Use Kesha's default output for OpenClaw's normal voice-message path: stdout is the bare transcript text, while progress and errors stay off the transcript payload. The default setup echoes each transcript back to chat as `🦜 "{transcript}"` before the agent responds.

For agents that need timestamped segments, switch the model entry to JSON output and allow a longer timeout:

```bash
openclaw config set tools.media.audio.models \
  '[{"type":"cli","command":"kesha","args":["--json","--timestamps","{{MediaPath}}"],"timeoutSeconds":30}]'
```

Verification checklist:

```bash
which kesha
kesha status
openclaw plugins list
openclaw config get tools.media.audio.models
openclaw config get tools.media.audio.echoTranscript
openclaw config get tools.media.audio.echoFormat
```

Do not rely on `openclaw.plugin.json` to patch `tools.media.audio.models`; OpenClaw ignores non-schema fields such as `configPatch`. Keep the CLI route in user config.

For OpenClaw TTS replies, route the local TTS provider to Kesha OGG/Opus output. This is the Telegram-safe path:

```bash
openclaw config patch --stdin <<'JSON5'
{
  messages: {
    tts: {
      auto: "always",
      provider: "tts-local-cli",
      providers: {
        "tts-local-cli": {
          command: "kesha",
          args: ["say", "--format", "ogg-opus", "--out", "{{OutputPath}}", "{{Text}}"],
          outputFormat: "opus",
          timeoutMs: 120000,
        },
      },
    },
  },
}
JSON5
```

When invoking Kesha manually from an OpenClaw flow, write OGG/Opus into an OpenClaw-owned temp path, for example `kesha say --format ogg-opus --out /tmp/openclaw/reply.ogg "<text>"`, after ensuring the directory exists. The configured `tts-local-cli` provider should use OpenClaw's `{{OutputPath}}` placeholder instead of a hardcoded path.

Do not configure OpenClaw Telegram TTS as `kesha say "<text>" > reply.wav`; that creates a WAV file and will not render as a native Telegram voice note.

## MCP server

`kesha mcp` serves the same capabilities over Model Context Protocol (stdio), exposing `transcribe_audio`, `synthesize_speech`, `list_voices`, and `list_languages` to any MCP client:

```json
{ "mcpServers": { "kesha": { "command": "kesha", "args": ["mcp"] } } }
```

Models are never auto-downloaded — tools fail with a `kesha install` / `kesha install --tts` hint when missing. Full client setup (Claude Code, Claude Desktop, Codex, Cursor): [docs/mcp.md](docs/mcp.md).

## STT: transcribe audio

```bash
# JSON output with language detection (recommended for automation)
kesha --json voice.ogg
```

```json
[{
  "file": "voice.ogg",
  "text": "Привет, как дела?",
  "lang": "ru",
  "audioLanguage": { "code": "ru", "confidence": 0.98 },
  "textLanguage": { "code": "ru", "confidence": 0.99, "source": "engine" }
}]
```

Use `lang` (or the more detailed `audioLanguage`/`textLanguage`) to decide how to respond.

**Read `textLanguage.source` before you compare its `confidence` to a threshold.** `"engine"` (macOS `NLLanguageRecognizer`) and `"tinyld"` (the CLI fallback used on Linux/Windows) score on different scales — the same correct detection reads ~0.98 from the engine and ~0.2 from `tinyld`, so a fixed `> 0.5` gate discards every correct fallback result. `audioLanguage` has one detector and carries no `source`.

Need timestamped transcript segments for navigation, chapters, or downstream editing:

```bash
kesha --json --timestamps voice.ogg > voice.timestamps.json
jq '.[0].segments' voice.timestamps.json
```

Each segment has `start`, `end`, and `text` fields. `--timestamps` is available for machine-readable output (`--json`, `--toon`, or `--format json`).

**Speaker diarization** (darwin-arm64, post-v1.12.0). Add `--speakers` to label each segment with a cluster ID — useful for transcribing multi-person calls / meetings:

```bash
kesha install --diarize                                  # one-time, ~245MB (installs VAD too)
kesha --json --speakers meeting.m4a > out.json           # --speakers engages VAD itself
jq '.[0].segments[] | "\(.speaker)\t\(.text)"' out.json
```

Each `segment.speaker` is a number (cluster id, stable within one file). `--speakers` forces VAD windowing at any duration, so it cannot be combined with `--no-vad`. On Linux / Windows the engine returns a clear "currently darwin-arm64 only" error — see [#199](https://github.com/drakulavich/kesha-voice-kit/issues/199).

**Formats:** .ogg, .opus, .mp3, .m4a, .wav, .flac, .webm — decoded via symphonia, no ffmpeg required.

**Other output modes:**
- `kesha audio.ogg` — plain transcript on stdout
- `kesha --format transcript audio.ogg` — transcript + `[lang: ru, confidence: 0.99]` footer
- `kesha --json --timestamps audio.ogg` — JSON with timestamped `segments`
- `kesha --toon audio.ogg` — TOON (compact, LLM-friendly JSON encoding); preferred when piping multi-file results to an LLM/agent
- `kesha --verbose audio.ogg` — human-readable with language info
- `kesha --lang en audio.ogg` — warn if detected language differs (useful sanity check)

**Long audio:** files ≥ 120 s auto-engage Silero VAD chunking; force on with `--vad` or off with `--no-vad`. Short files use full-file ASR by default.

## TTS: synthesize speech

```bash
kesha say "Hello, world" > hello.wav               # auto-routes en → Kokoro-82M
kesha say "Привет, мир" > privet.wav              # auto-routes ru → Vosk-TTS
kesha say --voice macos-de-DE "Guten Tag" > de.wav # any macOS system voice — German, French, Italian, ...
kesha say --list-voices                            # Kokoro + Vosk-TTS + ~180 macos-* voices
```

Output: WAV mono float32 by default. `--out <path>` writes to a file instead of stdout. For Telegram/OpenClaw replies, prefer `--format ogg-opus --out reply.ogg` or the OpenClaw-provided `{{OutputPath}}`.

**Output formats** (`--format`, or inferred from the `--out` extension): `wav` (default, uncompressed), `ogg-opus` (messenger voice notes), `flac` (lossless, royalty-free, plays in every browser incl. Safari/iOS — the format for web-embeddable samples). FLAC keeps the engine's native rate; `--bitrate` / `--sample-rate` apply only to `ogg-opus`.

```bash
kesha say --format flac --out sample.flac "Hello"   # web-embeddable, Safari-safe
```

**Voice notes (Telegram / WhatsApp / Signal / Discord):** add `--format ogg-opus` to emit OGG/Opus directly — the format messenger APIs render as a native voice message:

```bash
kesha say --format ogg-opus --out reply.ogg "Hello there"                  # 24 kHz @ 32 kbps mono - Telegram-grade
kesha say --voice ru-vosk-m02 --format ogg-opus --out reply.ogg "Привет"   # Russian voice note
kesha say --format ogg-opus --bitrate 16000 --out tiny.ogg "Hi"            # tinier file, intelligible but lossy
```

Format is also inferred from `--out` extension (`.ogg` / `.opus` / `.oga` → OGG/Opus). `--bitrate` (6 000–510 000 bps) and `--sample-rate` (8 000 / 12 000 / 16 000 / 24 000 / 48 000 Hz) tune the encoder.

**Russian abbreviations** (`ru-vosk-*`): all-uppercase Cyrillic 2-5-char tokens auto-expand letter-by-letter when not pronounceable as a Russian syllable (ФСБ → "эф-эс-бэ", ВОЗ → "воз"). Disable with `--no-expand-abbrev`. See [docs/tts.md#russian-abbreviation-auto-expansion](docs/tts.md#russian-abbreviation-auto-expansion).

**English acronyms** (`en-*`, Kokoro): three-table mechanism (letter-spell rule + STOP_LIST + IPA_LEXICON) auto-expands FBI → "ef bee eye" and gives EPAM/JSON/Anthropic the right IPA. Disable letter-spell with `--no-expand-abbrev` — honored on ONNX builds only; the released darwin-arm64 binary spells initialisms inside FluidAudio's own G2P and warns that the flag is a no-op ([#842](https://github.com/drakulavich/kesha-voice-kit/issues/842)). See [docs/tts.md#english-acronym-auto-expansion](docs/tts.md#english-acronym-auto-expansion).

**Russian word stress** (`ru-vosk-*` only): `<emphasis>сл+ово</emphasis>` shifts stress to the vowel marked with `+`. `<emphasis level="none">сл+ово</emphasis>` strips the `+` (cancel inherited emphasis). Other voices (`en-*`, `macos-*`) silently strip the `+` and warn once per process. Auto-stress dictionary not provided — caller writes the `+` manually. Closes [#233](https://github.com/drakulavich/kesha-voice-kit/issues/233).

**Speech rate via SSML** (`ru-vosk-*` and `en-*` voices): wrap the utterance in `<prosody rate="…">` to slow down or speed up synthesis. Supports SSML named values (`x-slow`/`slow`/`medium`/`fast`/`x-fast`), absolute `N%` (e.g. `120%`), and relative `+N%`/`-N%`. Honored only when `<prosody>` wraps the whole utterance — mid-utterance prosody warns and synthesizes at default rate. `--rate` and `<prosody rate>` compose multiplicatively; result is clamped to 0.5×–2.0×. AVSpeech (`macos-*` voices) does not yet accept SSML — see [#236](https://github.com/drakulavich/kesha-voice-kit/issues/236).

## Language detection standalone

`kesha --json audio.ogg` includes both audio-based (`audioLanguage`) and text-based (`textLanguage`) detection. Use audio detection to identify the language before running language-specific logic. `textLanguage` also names its detector in `source` — see the threshold rule under [STT](#stt-transcribe-audio).

## Install

**Humans use `kesha init` (guided). Agents and scripts use `kesha install` (deterministic).**

```bash
bun add -g @drakulavich/kesha-voice-kit          # global CLI install (always first)

# For humans: interactive setup that prompts for backend / TTS / VAD / diarize
kesha init

# For agents and CI: explicit, scriptable install commands
kesha install                                    # engine only — ~0.6 GB on Apple Silicon, ~2.5 GB on Linux/Windows
kesha install --plan                             # preview exact download/disk sizes first — downloads nothing
kesha install --tts                              # + English Kokoro; add langs additively: --tts en ru es
kesha install --tts --vad                        # + Silero VAD (long-audio chunking)
kesha install --tts --diarize                    # + speaker diarization, VAD included (darwin-arm64 only)
```

Kesha's runtime error/warning messages adapt to the same split: when `kesha` is invoked from a TTY, hints suggest `kesha init`; when stderr is piped (CI logs, OpenClaw, agent subprocess), hints suggest the equivalent `kesha install [...flags]`. Both run the same install code under the hood — pick the one your caller is.

For pre-release builds: `bun add -g @drakulavich/kesha-voice-kit@beta` (current `beta` channel; `@latest` stays on the last stable release).

No system deps — English G2P is embedded (`misaki-rs`); Russian G2P is bundled inside Vosk-TTS. `macos-*` voices need no install either — they use voices already on the Mac.

## Supported languages

**Speech-to-text (25):** Bulgarian, Croatian, Czech, Danish, Dutch, English, Estonian, Finnish, French, German, Greek, Hungarian, Italian, Latvian, Lithuanian, Maltese, Polish, Portuguese, Romanian, Russian, Slovak, Slovenian, Spanish, Swedish, Ukrainian.

**Text-to-speech (9):** English (Kokoro-82M; FluidAudio CoreML on darwin-arm64, ONNX elsewhere), Russian (Vosk-TTS, 5 baked-in speakers — default `ru-vosk-m02`), Spanish, French, Italian, Portuguese (Kokoro — CharsiuG2P on ONNX builds, FluidAudio G2P on darwin-arm64), plus Hindi, Japanese, Chinese (Kokoro, darwin-arm64 only). The `hi`/`ja` Kokoro voices read romanized Latin input only; on macOS, text that is mostly Devanagari or kana/kanji with no `--voice` routes to an installed AVSpeech voice (Lekha for `hi-IN`, Otoya for `ja-JP`), while an explicit `--voice hi-*`/`ja-*` refuses them with `E_SCRIPT_UNSUPPORTED`; non-macOS builds have no `hi`/`ja` voices, so the text is refused by the default English voice (`E_SCRIPT_UNSUPPORTED`) and `--voice hi-*`/`ja-*` is `E_VOICE_UNKNOWN` — see [#492](https://github.com/drakulavich/kesha-voice-kit/issues/492). Any macOS system voice is also available via `--voice macos-*`.

## Performance

- ASR: ~19× faster than OpenAI Whisper on Apple Silicon (CoreML via FluidAudio), ~2.5× on CPU (ONNX via `ort`).
- TTS: sub-second latency for short utterances on Apple Silicon.

## Troubleshooting

- `kesha doctor` — collect support diagnostics without changing local state. Add `--json` for machine-readable output, `--redact` to scrub secrets and home paths before sharing.
- `kesha logs` — manage privacy-safe local diagnostic logs. Default mode is `retain-on-failure` (events buffered in memory, flushed to disk only when a command fails). `kesha logs mode on` captures every run, `kesha logs path` prints the NDJSON file, `kesha logs disable` turns it off entirely.
- `kesha support-bundle --output bundle.tar.gz` — produce a redacted `.tar.gz` for filing an issue. Add `--include-logs` to bundle a bounded tail of diagnostic logs.
- `kesha stats` — manage local anonymous performance stats (per-command latency percentiles). Actions: `enable | disable | status | week | errors | export | reset | vacuum | retention`. Stays on the machine.

## Why local

No API keys to manage. No per-minute billing. Voice data never leaves the machine — important for regulated industries, personal messaging, and anything that shouldn't be in a third-party log.

## Links

- Source: https://github.com/drakulavich/kesha-voice-kit
- npm: https://www.npmjs.com/package/@drakulavich/kesha-voice-kit
- Releases: https://github.com/drakulavich/kesha-voice-kit/releases