SuperCollider MCP Server

Instructions

Implementation Reference

• src/index.ts:351-389 (handler)

  Handler for sc_play_synth_advanced: validates input parameters using Zod, checks if SuperCollider server is booted, constructs dynamic Synth SuperCollider code with provided synthName and parameters, executes it via scServer.executeCode, and returns confirmation.
  case 'sc_play_synth_advanced': { const schema = z.object({ synthName: z.string(), freq: z.number().optional(), amp: z.number().optional(), duration: z.number().optional(), pan: z.number().optional(), decay: z.number().optional(), cutoff: z.number().optional(), startFreq: z.number().optional(), endFreq: z.number().optional(), }); const params = schema.parse(args); if (!scServer.getBooted() || !synthDefsLoaded) { return { content: [{ type: 'text', text: 'Error: SuperCollider server is not running. Call sc_boot first.' }], isError: true, }; } const { synthName, ...synthParams } = params; const paramStr = Object.entries(synthParams) .filter(([_, value]) => value !== undefined) .map(([key, value]) => `\\${key}, ${value}`) .join(', '); const code = `Synth(\\${synthName}, [${paramStr}]);`; await scServer.executeCode(code); return { content: [ { type: 'text', text: `Playing ${synthName} synth with parameters: ${JSON.stringify(synthParams)}`, }, ], }; }
• src/index.ts:96-142 (registration)

  Tool registration object for sc_play_synth_advanced, including full input schema with parameter definitions and enum for synthName matching available SynthDefs.
  { name: 'sc_play_synth_advanced', description: 'Play a specific synth with explicit parameters. Available synths: sine, pluck, bell, bass, pad, kick, snare, hihat, atmosphere, sweep', inputSchema: { type: 'object', properties: { synthName: { type: 'string', description: 'Name of the synth to play', enum: ['sine', 'pluck', 'bell', 'bass', 'pad', 'kick', 'snare', 'hihat', 'atmosphere', 'sweep'], }, freq: { type: 'number', description: 'Frequency in Hz (default: 440)', }, amp: { type: 'number', description: 'Amplitude 0-1 (default: 0.3)', }, duration: { type: 'number', description: 'Duration in seconds (default: 1)', }, pan: { type: 'number', description: 'Pan position -1 (left) to 1 (right) (default: 0)', }, decay: { type: 'number', description: 'Decay time for pluck synth (default: 2)', }, cutoff: { type: 'number', description: 'Filter cutoff frequency for bass/pad (default: varies)', }, startFreq: { type: 'number', description: 'Start frequency for sweep (default: 100)', }, endFreq: { type: 'number', description: 'End frequency for sweep (default: 2000)', }, }, required: ['synthName'], }, },
• src/index.ts:99-140 (schema)

  Detailed input schema for sc_play_synth_advanced tool defining all parameters, types, descriptions, defaults implied, and required synthName with exact enum of supported synths.
  inputSchema: { type: 'object', properties: { synthName: { type: 'string', description: 'Name of the synth to play', enum: ['sine', 'pluck', 'bell', 'bass', 'pad', 'kick', 'snare', 'hihat', 'atmosphere', 'sweep'], }, freq: { type: 'number', description: 'Frequency in Hz (default: 440)', }, amp: { type: 'number', description: 'Amplitude 0-1 (default: 0.3)', }, duration: { type: 'number', description: 'Duration in seconds (default: 1)', }, pan: { type: 'number', description: 'Pan position -1 (left) to 1 (right) (default: 0)', }, decay: { type: 'number', description: 'Decay time for pluck synth (default: 2)', }, cutoff: { type: 'number', description: 'Filter cutoff frequency for bass/pad (default: varies)', }, startFreq: { type: 'number', description: 'Start frequency for sweep (default: 100)', }, endFreq: { type: 'number', description: 'End frequency for sweep (default: 2000)', }, }, required: ['synthName'],
• src/synth-library.ts:127-129 (helper)

  Helper function to generate initialization code that concatenates all SynthDef definitions for the synths used in sc_play_synth_advanced (must be executed via sc_execute after boot).
  export function getSynthDefInitCode(): string { return Object.values(SYNTH_DEFS).join('\n\n'); }
• src/synth-library.ts:14-122 (helper)

  Collection of SuperCollider SynthDef source code strings for all synths supported by sc_play_synth_advanced (sine, pluck, etc.), defining the actual sound generation logic with parameters matching the tool schema.
  export const SYNTH_DEFS = { // Simple sine wave tone sine: ` SynthDef(\\sine, { |freq=440, amp=0.3, pan=0, gate=1| var sig = SinOsc.ar(freq, 0, amp); var env = EnvGen.kr(Env.asr(0.01, 1, 0.1), gate, doneAction: 2); Out.ar(0, Pan2.ar(sig * env, pan)); }).add; `, // Plucked string sound pluck: ` SynthDef(\\pluck, { |freq=440, amp=0.3, pan=0, decay=2| var sig = Pluck.ar( WhiteNoise.ar(amp), Impulse.kr(0), freq.reciprocal, freq.reciprocal, decay, coef: 0.1 ); var env = EnvGen.kr(Env.linen(0, decay, 0), doneAction: 2); Out.ar(0, Pan2.ar(sig * env, pan)); }).add; `, // Bell-like FM tone bell: ` SynthDef(\\bell, { |freq=440, amp=0.3, pan=0, duration=2| var modulator = SinOsc.ar(freq * 2.4, 0, freq * 0.8); var carrier = SinOsc.ar(freq + modulator, 0, amp); var env = EnvGen.kr(Env.perc(0.01, duration, 1, -4), doneAction: 2); Out.ar(0, Pan2.ar(carrier * env, pan)); }).add; `, // Bass tone bass: ` SynthDef(\\bass, { |freq=110, amp=0.4, pan=0, duration=1, cutoff=1000| var sig = LPF.ar(Saw.ar(freq), cutoff); var env = EnvGen.kr(Env.perc(0.01, duration), doneAction: 2); Out.ar(0, Pan2.ar(sig * env * amp, pan)); }).add; `, // Pad sound pad: ` SynthDef(\\pad, { |freq=220, amp=0.2, pan=0, gate=1, cutoff=2000| var sig = RLPF.ar( Saw.ar([freq, freq * 1.01], amp), cutoff, 0.5 ); var env = EnvGen.kr(Env.asr(0.5, 1, 2), gate, doneAction: 2); Out.ar(0, Pan2.ar(Mix(sig) * env, pan)); }).add; `, // Kick drum kick: ` SynthDef(\\kick, { |amp=0.5, pan=0| var freqEnv = EnvGen.kr(Env.perc(0.001, 0.3), 1, 60, 50); var sig = SinOsc.ar(freqEnv, 0, amp); var env = EnvGen.kr(Env.perc(0.001, 0.5), doneAction: 2); Out.ar(0, Pan2.ar(sig * env, pan)); }).add; `, // Snare drum snare: ` SynthDef(\\snare, { |amp=0.3, pan=0| var sig = WhiteNoise.ar(amp) + SinOsc.ar(180, 0, amp); var env = EnvGen.kr(Env.perc(0.001, 0.2), doneAction: 2); Out.ar(0, Pan2.ar(sig * env, pan)); }).add; `, // Hi-hat hihat: ` SynthDef(\\hihat, { |amp=0.2, pan=0| var sig = HPF.ar(WhiteNoise.ar(amp), 8000); var env = EnvGen.kr(Env.perc(0.001, 0.1), doneAction: 2); Out.ar(0, Pan2.ar(sig * env, pan)); }).add; `, // Atmospheric noise atmosphere: ` SynthDef(\\atmosphere, { |amp=0.15, pan=0, gate=1, cutoff=3000| var sig = RHPF.ar( PinkNoise.ar(amp), LFNoise1.kr(0.5).range(cutoff * 0.5, cutoff), 0.2 ); var env = EnvGen.kr(Env.asr(2, 1, 3), gate, doneAction: 2); Out.ar(0, Pan2.ar(sig * env, pan)); }).add; `, // Sweep/riser sweep: ` SynthDef(\\sweep, { |startFreq=100, endFreq=2000, amp=0.3, pan=0, duration=2| var freq = Line.kr(startFreq, endFreq, duration); var sig = Saw.ar(freq, amp); var env = EnvGen.kr(Env.linen(0.1, duration - 0.2, 0.1), doneAction: 2); Out.ar(0, Pan2.ar(sig * env, pan)); }).add; `, };