Jsfxr MCP Server

An MCP server that provides tools to generate 8-bit retro sound effects (sfx) using the jsfxr library.

Prerequisite

• Node.js >= 16

Build

npm install
npm run build

Configuration

To use with MCP client, add this to your MCP configuration:

{
  "mcpServers": {
    "jsfxr": {
      "command": "node",
      "args": ["/path/to/jsfxr-mcp-wrapper/dist/index.js"]
    }
  }
}

Tools

generate_sound_preset

Generate a sound effect using a preset algorithm and save as WAV file.

Inputs:

• preset (string, required): one of pickupCoin, laserShoot, explosion, powerUp, hitHurt, jump, blipSelect, synth, tone, click, random.
• outputPath (string, required): Absolute path to save the output WAV file.

generate_sound_advanced

Generate a sound effect with detailed parameters and save as WAV file.

Inputs:

• outputPath (string, required): Absolute path to save the output WAV file.
• wave_type (number, optional): 0:square, 1:sawtooth, 2:sine, 3:noise.
• p_env_attack, p_env_decay, p_env_sustain, p_env_punch (number, optional): Envelope parameters.
• p_base_freq, p_freq_limit, p_freq_ramp, p_freq_dramp (number, optional): Frequency parameters.
• p_vib_strength, p_vib_speed (number, optional): Vibrato parameters.
• p_arp_mod, p_arp_speed (number, optional): Arpeggio parameters.
• p_duty, p_duty_ramp (number, optional): Duty cycle parameters.
• p_repeat_speed (number, optional): Repeat speed.
• p_pha_offset, p_pha_ramp (number, optional): Phaser parameters.
• p_lpf_freq, p_lpf_ramp, p_lpf_resonance (number, optional): Low-pass filter parameters.
• p_hpf_freq, p_hpf_ramp (number, optional): High-pass filter parameters.
• sound_vol (number, optional): Sound volume.
• sample_rate (number, optional): Default 44100.
• sample_size (number, optional): Default 8.

Output: Returns a text message confirming success.