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surgext-mcp

Surge XT synthesizer docs as an MCP server

Let AI models search parameters and assist with sound design.

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Demo

terminal
$ search_docs("wavetable oscillator")
> searching docs...
>
> Oscillators > Wavetable
> Morph — interpolates between wavetable frames
> Skew — asymmetrically shapes the playback
3 sections matched

Problem

Surge XT has hundreds of parameters across oscillators, filters, FX, and modulation. When asking an AI to help recreate a patch, the model has no reliable access to what each knob actually does.

What it is

surgext-mcp is a Model Context Protocol server that downloads, chunks, and indexes the official Surge XT documentation. It exposes four tools:

  • search_docs — full-text search across all docs
  • get_section — fetch content by heading path
  • get_parameter_info — look up a specific knob or control
  • list_sections — explore the document structure

Tools

Full-text Search

search_docs() finds relevant sections by keyword or concept.

Section Fetch

get_section() retrieves the full content of any heading path.

Parameter Lookup

get_parameter_info() returns exact knob and control documentation.

Structure Explorer

list_sections() exposes the full documentation hierarchy.

Architecture

Surge XT Docs
Ingest + Chunk
MCP Server
AI Model
Sound Design

Example tool call

Query

get_parameter_info("filter cutoff")

Response

Filter > Cutoff

Sets the cutoff frequency of the filter. Range: 13.75 Hz – 25.1 kHz.
Modulation target. Right-click to assign LFO, envelope, or MIDI CC.

Related: Resonance, Filter Type, Filter 2

Claude Desktop config

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

Why I Built This

I use Surge XT constantly but can never remember what the more obscure parameters do. Asking an AI for help meant the model was guessing from training data.

surgext-mcp gives the model authoritative documentation so it can actually help recreate patches accurately.

Repository

View on GitHub

Links