MCP FishAudio Server

Fish Audio MCP Server

An MCP (Model Context Protocol) server that provides seamless integration between Fish Audio's Text-to-Speech API and LLMs like Claude, enabling natural language-driven speech synthesis.

Features

🎙️ High-Quality TTS: Leverage Fish Audio's state-of-the-art TTS models
🌊 Streaming Support: Real-time audio streaming for low-latency applications
🎨 Multiple Voices: Support for custom voice models via reference IDs
🔧 Flexible Configuration: Environment variable-based configuration
📦 Multiple Audio Formats: Support for MP3, WAV, PCM, and Opus
🚀 Easy Integration: Simple setup with any MCP-compatible client

Quick Start

Installation

You can run this MCP server directly using npx:

npx @alanse/fish-audio-mcp-server

Or install it globally:

npm install -g @alanse/fish-audio-mcp-server

Configuration

Get your Fish Audio API key from Fish Audio
Set up environment variables:

export FISH_API_KEY=your_fish_audio_api_key_here

Add to your MCP settings configuration:

{
  "mcpServers": {
    "fish-audio": {
      "command": "npx",
      "args": ["-y", "@alanse/fish-audio-mcp-server"],
      "env": {
        "FISH_API_KEY": "your_fish_audio_api_key_here",
        "FISH_MODEL_ID": "s1",
        "FISH_REFERENCE_ID": "your_voice_reference_id_here",
        "FISH_OUTPUT_FORMAT": "mp3",
        "FISH_STREAMING": "false",
        "FISH_LATENCY": "balanced",
        "FISH_MP3_BITRATE": "128",
        "FISH_AUTO_PLAY": "false",
        "AUDIO_OUTPUT_DIR": "~/.fish-audio-mcp/audio_output"
      }
    }
  }
}

Environment Variables

Variable	Description	Default	Required
`FISH_API_KEY`	Your Fish Audio API key	-	Yes
`FISH_MODEL_ID`	TTS model to use (s1, speech-1.5, speech-1.6)	`s1`	Optional
`FISH_REFERENCE_ID`	Default voice reference ID	-	Optional
`FISH_OUTPUT_FORMAT`	Default audio format (mp3, wav, pcm, opus)	`mp3`	Optional
`FISH_STREAMING`	Enable streaming mode (HTTP/WebSocket)	`false`	Optional
`FISH_LATENCY`	Latency mode (normal, balanced)	`balanced`	Optional
`FISH_MP3_BITRATE`	MP3 bitrate (64, 128, 192)	`128`	Optional
`FISH_AUTO_PLAY`	Auto-play audio and enable real-time playback	`false`	Optional
`AUDIO_OUTPUT_DIR`	Directory for audio file output	`~/.fish-audio-mcp/audio_output`	Optional

Usage

Once configured, the Fish Audio MCP server provides the fish_audio_tts tool to LLMs.

Tool: `fish_audio_tts`

Generates speech from text using Fish Audio's TTS API.

Parameters

text (required): Text to convert to speech (max 10,000 characters)
reference_id (optional): Voice model reference ID
streaming (optional): Enable streaming mode
format (optional): Output format (mp3, wav, pcm, opus)
mp3_bitrate (optional): MP3 bitrate (64, 128, 192)
normalize (optional): Enable text normalization (default: true)
latency (optional): Latency mode (normal, balanced)
output_path (optional): Custom output file path
auto_play (optional): Automatically play the generated audio
websocket_streaming (optional): Use WebSocket streaming instead of HTTP
realtime_play (optional): Play audio in real-time during WebSocket streaming

Examples

Basic Text-to-Speech

User: "Generate speech saying 'Hello, world! Welcome to Fish Audio TTS.'"

Claude: I'll generate speech for that text using Fish Audio TTS.

[Uses fish_audio_tts tool with text parameter]

Result: Audio file saved to ./audio_output/tts_2025-01-03T10-30-00.mp3

Using Custom Voice

User: "Generate speech with voice model xyz123 saying 'This is a custom voice test'"

Claude: I'll generate speech using the specified voice model.

[Uses fish_audio_tts tool with text and reference_id parameters]

Result: Audio generated with custom voice model xyz123

HTTP Streaming Mode

User: "Generate a long speech in streaming mode about the benefits of AI"

Claude: I'll generate the speech in streaming mode for faster response.

[Uses fish_audio_tts tool with streaming: true]

Result: Streaming audio saved to ./audio_output/tts_2025-01-03T10-35-00.mp3

WebSocket Real-time Streaming

User: "Stream and play in real-time: 'Welcome to the future of AI'"

Claude: I'll stream the speech via WebSocket and play it in real-time.

[Uses fish_audio_tts tool with websocket_streaming: true, realtime_play: true]

Result: Audio streamed and played in real-time via WebSocket

Development

Local Development

Clone the repository:

git clone https://github.com/da-okazaki/mcp-fish-audio-server.git
cd mcp-fish-audio-server

Install dependencies:

npm install

Create .env file:

cp .env.example .env
# Edit .env with your API key

Build the project:

npm run build

Run in development mode:

npm run dev

Testing

Run the test suite:

npm test

Project Structure

mcp-fish-audio-server/
├── src/
│   ├── index.ts          # MCP server entry point
│   ├── tools/
│   │   └── tts.ts        # TTS tool implementation
│   ├── services/
│   │   └── fishAudio.ts  # Fish Audio API client
│   ├── types/
│   │   └── index.ts      # TypeScript definitions
│   └── utils/
│       └── config.ts     # Configuration management
├── tests/                # Test files
├── audio_output/         # Default audio output directory
├── package.json
├── tsconfig.json
└── README.md

API Documentation

Fish Audio Service

The service provides two main methods:

generateSpeech: Standard TTS generation
- Returns audio buffer
- Suitable for short texts
- Lower memory usage
generateSpeechStream: Streaming TTS generation
- Returns audio stream
- Suitable for long texts
- Real-time processing

Error Handling

The server handles various error scenarios:

INVALID_API_KEY: Invalid or missing API key
NETWORK_ERROR: Connection issues with Fish Audio API
INVALID_PARAMS: Invalid request parameters
QUOTA_EXCEEDED: API rate limit exceeded
SERVER_ERROR: Fish Audio server errors

Troubleshooting

Common Issues

"FISH_API_KEY environment variable is required"
- Ensure you've set the FISH_API_KEY environment variable
- Check that the API key is valid
"Network error: Unable to reach Fish Audio API"
- Check your internet connection
- Verify Fish Audio API is accessible
- Check for proxy/firewall issues
"Text length exceeds maximum limit"
- Split long texts into smaller chunks
- Maximum supported length is 10,000 characters
Audio files not appearing
- Check the AUDIO_OUTPUT_DIR path exists
- Ensure write permissions for the directory

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Fork the repository
Create your feature branch (git checkout -b feature/AmazingFeature)
Commit your changes (git commit -m 'Add some AmazingFeature')
Push to the branch (git push origin feature/AmazingFeature)
Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

Fish Audio for providing the excellent TTS API
Anthropic for creating the Model Context Protocol
The MCP community for inspiration and examples

Support

For issues, questions, or contributions, please visit the GitHub repository.

Changelog

v0.5.4 (2025-01-03)

Fixed zod version compatibility issues
Resolved dependency conflicts between MCP SDK and Fish Audio SDK
Verified local dev and build functionality

v0.5.3 (2025-01-03)

Fixed missing zod dependency causing module resolution errors
Improved compatibility when running via npx

v0.5.2 (2025-01-03)

Fixed audio playback issue with FISH_STREAMING=true
Fixed tilde (~) expansion in AUDIO_OUTPUT_DIR
Improved stability by separating HTTP and WebSocket streaming

v0.5.1 (2025-01-03)

Improved documentation formatting and clarity
Updated environment variables table for better readability
Made documentation more generic for all MCP clients

v0.5.0 (2025-01-03)

Simplified environment variables: removed FISH_WEBSOCKET_STREAMING and FISH_REALTIME_PLAY
WebSocket streaming now controlled by FISH_STREAMING
Real-time playback now controlled by FISH_AUTO_PLAY
Cleaner configuration with unified controls

v0.4.1 (2025-01-03)

Added intelligent environment variable mapping
FISH_WEBSOCKET_STREAMING defaults to FISH_STREAMING
FISH_REALTIME_PLAY defaults to FISH_AUTO_PLAY
Simplified configuration with smart defaults

v0.4.0 (2025-01-03)

Refactored to use official Fish Audio SDK
Improved WebSocket streaming implementation
Fixed auto-play functionality
Better error handling and connection stability
Latency parameter now properly supported (normal/balanced)
Cleaner codebase with SDK integration

v0.3.0 (2025-01-03)

Added WebSocket streaming support for real-time TTS
Added real-time audio playback during WebSocket streaming
New parameters: websocket_streaming and realtime_play
Support for both HTTP and WebSocket streaming modes
Real-time player for immediate audio output

v0.2.0 (2025-01-03)

Added automatic audio playback feature with auto_play parameter
Added FISH_AUTO_PLAY environment variable for default behavior
Support for cross-platform audio playback (macOS, Windows, Linux)
HTTP streaming mode implementation

v0.1.2 (2025-01-03)

Changed npm package name to @alanse/fish-audio-mcp-server

v0.1.1 (2025-01-03)

Fixed directory creation error when running via npx
Changed default audio output to user's home directory

v0.1.0 (2025-01-03)

Initial release
Basic TTS functionality
Streaming support
Environment variable configuration
Multiple audio format support

This server cannot be installed

security - not tested

license - permissive license

quality - not tested

How are these scores calculated?

remote-capable server

The server can be hosted and run remotely because it primarily relies on remote services or has no dependency on the local environment.