Adds Text-to-Speech to things like Claude Desktop and Cursor IDE.

It registers four TTS tools:

• say_tts
• elevenlabs_tts
• google_tts
• openai_tts

Uses the macOS say binary to speak the text with built-in system voices

Uses the ElevenLabs text-to-speech API to speak the text with premium AI voices

Uses Google's Gemini TTS models to speak the text with 30 high-quality voices. Available voices include:

Achernar, Achird, Algenib, Algieba, Alnilam, Aoede, Autonoe, Callirrhoe, Charon, Despina, Enceladus, Erinome, Fenrir, Gacrux, Iapetus, Kore, Laomedeia, Leda, Orus, Puck, Pulcherrima, Rasalgethi, Sadachbia, Sadaltager, Schedar, Sulafat, Umbriel, Vindemiatrix, Zephyr, Zubenelgenubi

Uses OpenAI's Text-to-Speech API to speak the text with 10 natural-sounding voices:

• alloy (Warm, conversational, modern)
• ash (Confident, assertive, slightly textured)
• ballad (Gentle, melodious, slightly lyrical)
• coral (Cheerful, fresh, upbeat)
• echo (Neutral, calm, balanced)
• fable (Storyteller-like, expressive)
• nova (Clear, precise, slightly formal)
• onyx (Deep, authoritative, resonant)
• sage (Soothing, empathetic, reassuring)
• shimmer (Bright, animated, playful)
• verse (Versatile, expressive)

Supports three quality models:

• gpt-4o-mini-tts - Default, optimized quality and speed
• tts-1 - Standard quality, faster generation
• tts-1-hd - High definition audio, premium quality

Additional features:

• Speed control from 0.25x to 4.0x (default: 1.0x)
• Custom voice instructions (e.g., "Speak in a cheerful and positive tone") via parameter or OPENAI_TTS_INSTRUCTIONS environment variable

By default, the TTS server enforces sequential speech operations - only one TTS request can play audio at a time. This prevents multiple agents from speaking simultaneously and creating an unintelligible cacophony. Subsequent requests will wait in a queue until the current speech completes.

Multi-Instance Protection: The mutex works both within a single MCP server process and across multiple Claude Desktop instances. When running multiple Claude Desktop terminals, they coordinate via a system-wide file lock to prevent overlapping speech.

To allow concurrent TTS operations (multiple speeches playing simultaneously):

Environment Variable:

export MCP_TTS_ALLOW_CONCURRENT=true

Command Line Flag:

mcp-tts --sequential-tts=false

Note: Concurrent TTS may result in overlapping audio that's difficult to understand. Use this option only when you explicitly want multiple TTS operations to run simultaneously.

By default, TTS tools return a message like "Speaking: [text]" when speech completes. This can interfere with LLM responses. To suppress this output:

Environment Variable:

export MCP_TTS_SUPPRESS_SPEAKING_OUTPUT=true

Command Line Flag:

mcp-tts --suppress-speaking-output

When enabled, tools return "Speech completed" instead of echoing the spoken text.

go install github.com/blacktop/mcp-tts@latest

❱ mcp-tts --help

TTS (text-to-speech) MCP Server.

Provides multiple text-to-speech services via MCP protocol:

• say_tts - Uses macOS built-in 'say' command (macOS only)
• elevenlabs_tts - Uses ElevenLabs API for high-quality speech synthesis
• google_tts - Uses Google's Gemini TTS models for natural speech
• openai_tts - Uses OpenAI's TTS API with various voice options

Each tool supports different voices, rates, and configuration options.
Requires appropriate API keys for cloud-based services.

Designed to be used with the MCP (Model Context Protocol).

Usage:
  mcp-tts [flags]

Flags:
  -h, --help                       help for mcp-tts
      --sequential-tts             Enforce sequential TTS (prevent concurrent speech) (default true)
      --suppress-speaking-output   Suppress 'Speaking:' text output
  -v, --verbose                    Enable verbose debug logging

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "say": {
      "command": "mcp-tts",
      "env": {
        "ELEVENLABS_API_KEY": "********",
        "ELEVENLABS_VOICE_ID": "1SM7GgM6IMuvQlz2BwM3",
        "GOOGLE_AI_API_KEY": "********",
        "OPENAI_API_KEY": "********",
        "OPENAI_TTS_INSTRUCTIONS": "Speak in a cheerful and positive tone",
        "MCP_TTS_SUPPRESS_SPEAKING_OUTPUT": "true",
        "MCP_TTS_ALLOW_CONCURRENT": "false"
      }
    }
  }
}

claude mcp add say \
  -e GOOGLE_AI_API_KEY=your_key \
  -e ELEVENLABS_API_KEY=your_key \
  -e OPENAI_API_KEY=your_key \
  -- mcp-tts

codex mcp add say \
  --env GOOGLE_AI_API_KEY=your_key \
  --env ELEVENLABS_API_KEY=your_key \
  --env OPENAI_API_KEY=your_key \
  -- mcp-tts

gemini mcp add say mcp-tts \
  -e GOOGLE_AI_API_KEY=your_key \
  -e ELEVENLABS_API_KEY=your_key \
  -e OPENAI_API_KEY=your_key

Or manually add to ~/.gemini/settings.json (or .gemini/settings.json in project root):

{
  "mcpServers": {
    "say": {
      "command": ["mcp-tts"],
      "env": {
        "GOOGLE_AI_API_KEY": "..."
      }
    }
  }
}

• ELEVENLABS_API_KEY: Your ElevenLabs API key (required for elevenlabs_tts)
• ELEVENLABS_VOICE_ID: ElevenLabs voice ID (optional, defaults to a built-in voice)
• GOOGLE_AI_API_KEY or GEMINI_API_KEY: Your Google AI API key (required for google_tts)
• OPENAI_API_KEY: Your OpenAI API key (required for openai_tts)
• OPENAI_TTS_INSTRUCTIONS: Custom voice instructions for OpenAI TTS (optional, e.g., "Speak in a cheerful and positive tone")
• MCP_TTS_SUPPRESS_SPEAKING_OUTPUT: Set to "true" to suppress "Speaking:" output (optional)
• MCP_TTS_ALLOW_CONCURRENT: Set to "true" to allow concurrent TTS operations (optional, defaults to sequential)

❱ cat test/say.json | go run main.go --verbose

2025/03/23 22:41:49 INFO Starting MCP server name="Say TTS Service" version=1.0.0
2025/03/23 22:41:49 DEBU Say tool called request="{Request:{Method:tools/call Params:{Meta:<nil>}} Params:{Name:say_tts Arguments:map[text:Hello, world!] Meta:<nil>}}"
2025/03/23 22:41:49 DEBU Executing say command args="[--rate 200 Hello, world!]"
2025/03/23 22:41:49 INFO Speaking text text="Hello, world!"

{"jsonrpc":"2.0","id":3,"result":{"content":[{"type":"text","text":"Speaking: Hello, world!"}]}}

❱ cat test/google_tts.json | go run main.go --verbose

2025/05/23 18:26:45 INFO Starting MCP server name="Say TTS Service" version=""
2025/05/23 18:26:45 DEBU Google TTS tool called request="{...}"
2025/05/23 18:26:45 DEBU Generating TTS audio model=gemini-2.5-flash-preview-tts voice=Kore text="Hello! This is a test of Google's TTS API. How does it sound?"
2025/05/23 18:26:49 INFO Playing TTS audio via beep speaker bytes=181006
2025/05/23 18:26:53 INFO Speaking via Google TTS text="Hello! This is a test of Google's TTS API. How does it sound?" voice=Kore

{"jsonrpc":"2.0","id":4,"result":{"content":[{"type":"text","text":"Speaking: Hello! This is a test of Google's TTS API. How does it sound? (via Google TTS with voice Kore)"}]}}

❱ cat test/openai_tts.json | go run main.go --verbose

2025/05/23 19:15:32 INFO Starting MCP server name="Say TTS Service" version=""
2025/05/23 19:15:32 DEBU OpenAI TTS tool called request="{...}"
2025/05/23 19:15:32 DEBU Generating OpenAI TTS audio model=tts-1 voice=nova speed=1.2 text="Hello! This is a test of OpenAI's text-to-speech API. I'm using the nova voice at 1.2x speed."
2025/05/23 19:15:34 DEBU Decoding MP3 stream from OpenAI
2025/05/23 19:15:34 DEBU Initializing speaker for OpenAI TTS sampleRate=22050
2025/05/23 19:15:36 INFO Speaking text via OpenAI TTS text="Hello! This is a test of OpenAI's text-to-speech API. I'm using the nova voice at 1.2x speed." voice=nova model=tts-1 speed=1.2

{"jsonrpc":"2.0","id":5,"result":{"content":[{"type":"text","text":"Speaking: Hello! This is a test of OpenAI's text-to-speech API. I'm using the nova voice at 1.2x speed. (via OpenAI TTS with voice nova)"}]}}

# Sequential mode (default) - speeches play one after another
cat test/sequential.json | go run main.go --verbose

# Concurrent mode - allows overlapping speech  
cat test/sequential.json | go run main.go --verbose --sequential-tts=false

This repo includes a speak skill that automatically announces plans, issues, and summaries aloud using TTS. Each project gets a unique voice so you can identify which project is speaking from another room.

Skills follow the Agent Skills open standard and work across Claude Code, Codex CLI, and Gemini CLI.

npx skills add https://github.com/blacktop/mcp-tts --skill speak

Via Plugin Marketplace (recommended):

claude plugin marketplace add blacktop/mcp-tts
claude plugin install speak@mcp-tts

Or manually:

mkdir -p ~/.claude/skills
git clone https://github.com/blacktop/mcp-tts.git /tmp/mcp-tts
cp -r /tmp/mcp-tts/skill ~/.claude/skills/speak

The skill is now available. Claude will use it automatically when relevant, or invoke directly with /speak.

Using the skill-installer (within a Codex session):

$skill-installer install the speak skill from https://github.com/blacktop/mcp-tts --path skill

Or manually:

mkdir -p ~/.codex/skills
git clone https://github.com/blacktop/mcp-tts.git /tmp/mcp-tts
cp -r /tmp/mcp-tts/skill ~/.codex/skills/speak

Restart Codex after installing.

Gemini CLI uses extensions to bundle skills. Install this repo as an extension:

gemini extensions install https://github.com/blacktop/mcp-tts.git

This installs the speak skill.

Or manually (skill only):

mkdir -p ~/.gemini/skills
git clone https://github.com/blacktop/mcp-tts.git /tmp/mcp-tts
cp -r /tmp/mcp-tts/skill ~/.gemini/skills/speak

Note: Gemini CLI skills are experimental. Enable via /settings → search "Skills" → toggle on.

To maintain one copy across all agents, run the install script:

git clone https://github.com/blacktop/mcp-tts.git
cd mcp-tts
./install-skill.sh

This copies the skill to ~/.agents/skills/speak and creates symlinks for Claude Code, Codex CLI, and Gemini CLI.

The skill triggers automatically after:

• Planning complete - When a plan/todo list is finalized
• Issue resolved - When a bug fix or error is resolved
• Summary generated - When completing a major task

Providers fallback in order: google → openai → elevenlabs → say (macOS). If a provider fails due to missing API keys, it's marked unavailable and skipped in future attempts.

MIT Copyright (c) 2025 blacktop