c339d2c324
Both speak surfaces built their GenerationRequest with a hardcoded "en" fallback and never consulted the resolved profile, so a profile created with language="fr" was still synthesised as English unless the caller passed language= explicitly. This hurts the MCP path most: an agent calling voicebox.speak has no way to know the bound profile's language, so it cannot pass the argument either. Every agent-triggered generation on a non-English profile came out with an English accent. The fallback chain is now explicit argument -> resolved profile's language -> "en", which matches how engine and personality already consult the resolved binding. The "en" backstop is kept so profiles with no language set behave exactly as before. Adds backend/tests/test_speak_language.py covering both surfaces: the fallback, explicit-argument precedence, and the unchanged "en" default. Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
Voicebox MCP server
Local Model Context Protocol server — lets any MCP-aware agent (Claude Code, Cursor, Windsurf, VS Code MCP extensions, etc.) speak text in your cloned voices, transcribe audio, and browse captures.
The server runs inside the same uvicorn process as the rest of Voicebox
and is mounted at /mcp (Streamable HTTP transport).
Install into your agent
Preferred — direct HTTP:
{
"mcpServers": {
"voicebox": {
"url": "http://127.0.0.1:17493/mcp",
"headers": { "X-Voicebox-Client-Id": "claude-code" }
}
}
}
Fallback — stdio shim (when the client doesn't speak HTTP MCP). The
voicebox-mcp binary ships inside the Voicebox.app bundle:
{
"mcpServers": {
"voicebox": {
"command": "/Applications/Voicebox.app/Contents/MacOS/voicebox-mcp",
"env": { "VOICEBOX_CLIENT_ID": "claude-code" }
}
}
}
Claude Code one-liner:
claude mcp add voicebox \
--transport http \
--url http://127.0.0.1:17493/mcp \
--header "X-Voicebox-Client-Id: claude-code"
Tools
| Name | Purpose |
|---|---|
voicebox.speak |
Speak text in a voice profile. Returns a generation id you can poll. |
voicebox.transcribe |
Whisper transcription of a base64 blob or an absolute local path. |
voicebox.list_captures |
Recent captures (dictation / recording / file) with transcripts. |
voicebox.list_profiles |
Available voice profiles (cloned + preset). |
All tools resolve voice profiles in this precedence:
- Explicit
profilearg (name or id — case-insensitive) - Per-client binding keyed by
X-Voicebox-Client-Id capture_settings.default_playback_voice_id(global default)
Bindings are managed via GET|PUT /mcp/bindings or in the app under
Settings → MCP.
Debug with MCP Inspector
npx @modelcontextprotocol/inspector http://127.0.0.1:17493/mcp
Point it at the URL, hit "List tools," call voicebox.list_profiles
first to confirm wiring, then voicebox.speak for end-to-end.
Non-MCP REST surface
POST /speak is a thin wrapper on the same code path for callers that
don't speak MCP (shell scripts, ACP, A2A):
curl -X POST http://127.0.0.1:17493/speak \
-H 'Content-Type: application/json' \
-H 'X-Voicebox-Client-Id: claude-code' \
-d '{"text":"Build complete.","profile":"Morgan"}'
Code layout
backend/mcp_server/
├── __init__.py # re-export mount_into
├── server.py # build_mcp_server() + mount_into(app)
├── tools.py # @mcp.tool() implementations
├── context.py # ClientIdMiddleware + current_client_id ContextVar
├── resolve.py # profile resolution precedence
├── events.py # pub/sub queue for /events/speak pill SSE
└── README.md # you are here
backend/mcp_shim/ # stdio ↔ Streamable-HTTP proxy (see its README)
The package is mcp_server, not mcp, to avoid shadowing the
installed mcp PyPI package that FastMCP imports internally.