Set up
Runs on your computer. Pick your agent and operating system.
Before you start
- Node.js 20 or newer
{
"mcpServers": {
"bfxr2-mcp": {
"command": "npx",
"args": [
"-y",
"bfxr2-mcp-server"
]
}
}
}same format Cursor, GitHub Copilot CLI, Junie, JetBrains AI Assistant, Augment (Auggie CLI), Factory Droid, Kiro, Devin CLI +12
Values in angle brackets are placeholders. Restart Claude Desktop after editing its config.Claude Desktop docs
README
synced Oct 26, 2026Bfxr2 MCP Server
A Model Context Protocol (MCP) server that provides music and sound effect generation tools using the existing Bfxr2 codebase.
Table of Contents
Features
- Sound Effect Generation: Create preset sound effects (pickup, laser, explosion, etc.)
- Custom Sound Creation: Full parameter control for custom sounds
- Random Generation: Generate random sounds with optional seeding
- WAV Export: Export generated sounds as WAV files (base64 or data URI)
- Parameter Inspection: View and modify sound parameters
- Zero Code Duplication: Uses existing Bfxr2 JavaScript files directly
Installation
cd mcp
npm install
MCP Server Configuration
To use the bfxr2 MCP server with Cline or other MCP clients, add this configuration:
{
"mcpServers": {
"bfxr2-music-generator": {
"autoApprove": [
"list_presets",
"get_parameters",
"generate_sound_effect",
"randomize_sound"
],
"disabled": false,
"timeout": 30,
"type": "stdio",
"command": "node",
"args": [
"/path/to/your/bfxr2/mcp/src/server.js"
]
}
}
}
Note: Update the path in args to match your actual bfxr2 installation directory.
Usage
Start the MCP Server
npm start
Available Tools
-
generate_sound_effect
- Generate preset sound effects
- Types: pickup, laser, explosion, powerup, hit, jump, blip
- Optional custom parameter overrides
-
generate_named_sound
- Generate sounds from precomputed named presets
- Presets: cry, pluck, splash, droplet, rip, woof, pushrock, glass, bark, powerdown, smallbark, bounce
- Each preset has carefully tuned parameters for specific sound characters
-
create_custom_sound
- Full control over all sound parameters
- Specify waveType, frequency, envelope, effects, etc.
-
create_sound_with_wave
- Create sounds using wave type by name
- Wave types: Square, Saw, Sin, White, Triangle, Rasp, Tan, Whistle, Breaker, Bitnoise, FMSyn, Voice
-
randomize_sound
- Generate completely random sounds
- Optional seed for reproducible results
-
mutate_sound
- Create variations of the last generated sound
- Slightly randomizes parameters while maintaining general character
-
export_wav
- Export last generated sound as WAV
- Formats: base64 or data URI
-
get_parameters
- View current sound parameters
-
list_presets
- List available generator presets (pickup, laser, etc.)
-
list_named_presets
- List available named presets with descriptions (cry, bark, splash, etc.)
-
list_wave_types
- List all available wave types with descriptions
Example Tool Calls
{
"name": "generate_sound_effect",
"arguments": {
"type": "laser",
"customParams": {
"frequency_start": 0.7,
"attackTime": 0.1
}
}
}
{
"name": "create_custom_sound",
"arguments": {
"parameters": {
"waveType": 2,
"frequency_start": 0.5,
"sustainTime": 0.3,
"vibratoDepth": 0.2
}
}
}
{
"name": "generate_named_sound",
"arguments": {
"preset": "bark",
"filepath": "/tmp/bark.wav"
}
}
{
"name": "create_sound_with_wave",
"arguments": {
"waveType": "Whistle",
"parameters": {
"frequency_start": 0.6,
"sustainTime": 0.4
},
"filepath": "/tmp/whistle.wav"
}
}
{
"name": "mutate_sound",
"arguments": {
"filepath": "/tmp/mutated.wav"
}
}
Architecture
The MCP server uses a lightweight wrapper approach:
- bfxr-wrapper.js: Provides minimal browser API mocks and loads existing Bfxr2 files
- server.js: MCP server implementation with tool handlers
- No code duplication: Directly imports from
../js/directory
Wave Types
| ID | Name | Description |
|---|---|---|
| 0 | Square | Classic square wave, good for retro game sounds |
| 1 | Saw | Sawtooth wave, raspy and buzzy |
| 2 | Sin | Pure sine wave, clean and simple |
| 3 | White | White noise, good for explosions and static |
| 4 | Triangle | Triangle wave, softer than square |
| 5 | Rasp | Periodic 1-bit noise, digital buzz |
| 6 | Tan | Tangent wave, potentially crazy/distorted |
| 7 | Whistle | Sin with overtone, breathy/hollow |
| 8 | Breaker | Quadratic wave, smooth and slick |
| 9 | Bitnoise | Periodic 1-bit white noise, glitchy |
| 10 | FMSyn | FM synthesis, dense and breathy |
| 11 | Voice | Digital voice sample |
Named Presets
Pre-configured sounds with carefully tuned parameters:
| Name | Wave Type | Description |
|---|---|---|
| cry | Voice | A crying/whimpering voice sound |
| pluck | Voice | A plucked string instrument sound |
| splash | Sin | A water splash effect |
| droplet | Whistle | A water droplet sound |
| rip | Voice | A tearing/ripping sound |
| woof | Square | A dog bark/woof sound |
| pushrock | White | A heavy object pushing/scraping sound |
| glass | Whistle | A glass breaking/tinkling sound |
| bark | Rasp | A sharp bark sound |
| powerdown | White | A power-down/shutdown sound |
| smallbark | Rasp | A small/quiet bark sound |
| bounce | FMSyn | A bouncy/springy sound |
Sound Parameters
Key parameters you can control:
waveType: Wave shape (0-11)frequency_start: Base frequency (0-1)frequency_slide: Frequency sweep (-0.5 to 0.5)attackTime: Volume envelope attack (0-1)sustainTime: Volume envelope sustain (0-1)decayTime: Volume envelope decay (0.03-1)vibratoDepth: Vibrato strength (0-1)vibratoSpeed: Vibrato speed (0-1)
Contributing
We welcome contributions! Please see CONTRIBUTING.md for guidelines on how to get started.
Changelog
See CHANGELOG.md for a list of changes in each version.
License
This project is licensed under the MIT License - see the LICENSE file for details.