voice-mcp

Voice MCP

Give Your Agent A Voice: x402 pay-per-call speech with 20 voices, 10 personas, 31 languages, granular speed and quality controls, OpenAI-shaped requests, and batch audio.

This MCP wraps https://voice.forgemesh.io, an x402 Voice API with standard voices, persona voices, OpenAI-shaped speech requests, 31 languages, speed controls, quality controls, and batch generation. Payments are made per call in USDC on Base.

Voice Coverage

• 10 standard voices: M1-M5, F1-F5
• 10 persona voices: Storyteller, Narrator, Announcer, Assistant, Urgent, Sage, Spark, Anchor, Velvet, Echo
• 31 languages: en, ko, ja, ar, bg, cs, da, de, el, es, et, fi, fr, hi, hr, hu, id, it, lt, lv, nl, pl, pt, ro, ru, sk, sl, sv, tr, uk, vi
• Granular control: speed 0.7x-2.0x, quality steps 1-100, persona selection, OpenAI-shaped audio format requests, and batch generation for up to 20 texts
• Voice samples are generated on demand by the paid speech tools and returned as audio_base64 WAV output

Voice Samples

• Assistant sample
• Urgent sample
• Narrator sample
• Storyteller sample

Tools

Tool	Price	Purpose
list_voice_catalog	Free	Voices, personas, languages, pricing, buckets, and controls
generate_standard_voice	$0.001 / $0.003	Low-cost speech with 10 standard voices
generate_controlled_voice	$0.003 / $0.006	Speech with granular speed and quality controls
generate_persona_voice	$0.005 / $0.01	Storyteller, Velvet, Narrator, Announcer, Assistant, Urgent, and more
generate_openai_compatible_voice	$0.001 / $0.003	OpenAI-shaped /v1/audio/speech request
generate_batch_voices	$0.002 / $0.005	Up to 20 texts per call

Short prices apply to 1-500 characters. Long prices apply to 501-2000 characters.

The MCP validates voice names, language codes, audio formats, speed/quality ranges, batch item count, and character limits locally before making a paid x402 call.

Install

npm install -g @forgemeshlabs/voice-mcp

Docker

Build:

docker build -t voice-mcp .

Run over stdio:

docker run --rm -i \
  -e WALLET_PRIVATE_KEY=0x... \
  voice-mcp

CMD arguments:

["node", "index.js"]

MCP Config

{
  "mcpServers": {
    "voice": {
      "command": "voice-mcp",
      "env": {
        "WALLET_PRIVATE_KEY": "0x..."
      }
    }
  }
}

Requirements and safety

• Use a dedicated, low-balance wallet; the server signs payments with WALLET_PRIVATE_KEY.
• The server refuses to sign for any payee other than the ForgeMesh Voice wallet, any network other than Base mainnet, any asset other than USDC, or any amount over the built-in per-call cap ($0.01).
• Optional env X402_MAX_PRICE_USD (per call) and X402_SESSION_BUDGET_USD (cumulative per process, default $10) can only LOWER the built-in caps.
• The backend URL is fixed to https://voice.forgemesh.io; all requests are same-origin, time-limited (60s), size-capped (2 MB) and never follow redirects.

Notes

• Paid tools require a Base wallet private key with USDC.
• The server returns audio_base64 for audio tools so MCP clients can store, play, or forward the WAV bytes.
• No API keys or subscriptions are required for the voice service itself.