MCP Kokoro Tts

mcp-kokoro-tts

Local Kokoro-82M text-to-speech MCP server. When your agent calls speak, it synthesizes speech and plays it on your machine so you can hear the harness talk.

Works with any MCP client: Claude Desktop, Claude Code, Cursor, VS Code, opencode, Cline, and more. One short config block, no API keys — synthesis runs locally with Kokoro-82M.

On first start, the server provisions two things that are not on PyPI: the Kokoro-82M weights (~312 MB) into a local cache, and spaCy's English model (en_core_web_sm) into the same Python environment the server is running in. That second install is required because Kokoro's G2P pipeline loads spaCy, and a uvx / uv tool environment will not have the model unless this package puts it there.

Install

Add to your client's MCP config:

{

"mcpServers": { "mcp-kokoro-tts": { "command": "uvx", "args": ["mcp-kokoro-tts"] } } }

Requires Python 3.12 and uv. The first server start provisions Kokoro weights and the spaCy English model automatically.

To pre-download both without starting the MCP server:

uvx mcp-kokoro-tts-provision

Make the agent call it

Add one line to your AGENTS.md / CLAUDE.md / system prompt:

When the user wants to hear something spoken aloud, call the `speak` tool with clear, natural text.

Tools

speak

Synthesizes speech, writes a WAV file, and plays it locally. Playback goes through a single queue: the call returns as soon as its audio is queued, and utterances play back to back in call order instead of overlapping.

list_voices

Lists available Kokoro voices and the currently selected default.

stop

Cuts the utterance playing right now and drops everything queued behind it. Same thing the hotkey below does, for clients that cannot press keys.

settings

Returns the local settings page URL, the current stop hotkey, and whether the keyboard listener is armed.

Stop hotkey (barge-in)

Hold Ctrl + Shift and playback stops immediately: the current sentence is cut and every queued utterance is discarded, so you can talk over the agent.

Change the chord on the local settings page the server prints at startup — http://127.0.0.1:8765/ by default — where you press the new combination and save. It is written to ~/.config/mcp-kokoro-tts/hotkey.json and picked up without a restart.

A global keyboard listener needs Input Monitoring permission on macOS: the server asks for it on startup, so the app running it shows up under System Settings → Privacy & Security → Input Monitoring — switch it on and restart. Without it the hotkey reports needs_input_monitoring; the stop tool and the page's "Stop audio now" button keep working.

Choosing your voice

Resolution order:

1. TTS_VOICE env var — voice id or absolute .pt path
2. A file in the package voices/ folder whose name starts with default
3. First .pt file in voices/ (alphabetical)
4. The model's bundled af_heart voice

{

"mcpServers": { "mcp-kokoro-tts": { "command": "uvx", "args": ["mcp-kokoro-tts"], "env": { "TTS_VOICE": "af_heart" } } } }

Shared server (one copy for many clients)

By default each MCP client starts its own server over stdio, so five open sessions load the model five times. Run one shared server over streamable HTTP instead:

TTS_TRANSPORT=http mcp-kokoro-tts        # or: mcp-kokoro-tts --http --port 8766

Then point clients at it:

{ "mcpServers": { "mcp-kokoro-tts": { "type": "http", "url": "http://127.0.0.1:8766/mcp" } } }

Every client then shares one model and one playback queue. TTS_HTTP_HOST (default 127.0.0.1) and TTS_HTTP_PORT (default 8766) set the address.

Environment variables

Platforms

espeak-ng is optional. English works without it; install it for better out-of-vocabulary coverage and some non-English languages.

Publishing

Tagging a version runs GitHub Actions publish.yml, which uploads to PyPI then the MCP Registry.

Publishing to PyPI uses the repo secret PYPI_TOKEN (a PyPI API token). GitHub trusted publishing can also be configured on the PyPI project; this workflow authenticates with the token so a first release does not depend on pending-publisher matching.

Release

1. Bump version in pyproject.toml (and server.json if you are not tagging yet)
2. Commit and tag: git tag v0.1.2 && git push origin v0.1.2
3. GitHub Actions runs publish.yml:

• release — typecheck, test, build wheel/sdist
• pypi-publish — upload to PyPI with PYPI_TOKEN
• mcp-registry — OIDC → MCP Registry (after PyPI succeeds)

Development

cd mcps-tts

python3.12 -m venv .venv source .venv/bin/activate pip install -e ".[dev]" pyright pytest python -m mcp_kokoro_tts

License

Apache-2.0. See LICENSE and NOTICE. Kokoro-82M model weights are downloaded separately under their Apache-2.0 license.