Fallreach

MCP server for foldkit — exposes the 7-prime spine, 7 κ-bands, and 6 fold operations as native tools + resources in any MCP client (Claude Code, Claude Desktop, Cursor, Cline, Windsurf, etc.).

Second canonical exemplar of the AI-Native Solutions estate -mcp companion shape. Fork this repo verbatim to build companions for any of the ~295 estate substrates.

• Package: @ai-native-solutions/fallreach-mcp
• Transport: stdio
• Deps: @modelcontextprotocol/sdk + @ai-native-solutions/fallreach-sdk
• License: MIT

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Install

Claude Code

claude mcp add foldkit -- npx -y @ai-native-solutions/fallreach-mcp

Claude Desktop

Edit ~/AppData/Roaming/Claude/claude_desktop_config.json (Windows) or ~/Library/Application Support/Claude/claude_desktop_config.json (macOS):

{
  "mcpServers": {
    "foldkit": {
      "command": "npx",
      "args": ["-y", "@ai-native-solutions/fallreach-mcp"]
    }
  }
}

Cursor

Create or edit .cursor/mcp.json:

{
  "mcpServers": {
    "foldkit": {
      "command": "npx",
      "args": ["-y", "@ai-native-solutions/fallreach-mcp"]
    }
  }
}

Cline / Windsurf

Add to your MCP settings JSON:

{
  "mcpServers": {
    "foldkit": {
      "command": "npx",
      "args": ["-y", "@ai-native-solutions/fallreach-mcp"]
    }
  }
}

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Tools exposed (10)

Tool	Purpose
foldkit_fold_number	7-vector → primorial fold + signature
foldkit_unfold_state	fold integer → 7-vector via 7-prime factorisation
foldkit_depth_band	κ → named band (ground / perception / gate / heart / naming / recognition / collapse)
foldkit_classify_kappa_band	free-text utterance → κ band via marker phrases
foldkit_apply_op	apply fire / water / void / thunder / echo / flower to a state
foldkit_kawasaki_check	flat-fold angle sum check
foldkit_maekawa_check	mountain-valley parity check ( | M − V | = 2 )
foldkit_signal_survival	κ^depth signal survival + %
foldkit_unclog_gain	gain from clearing N layers of a κ stack
foldkit_probe_from_kappa	κ or text → band + routing op + probe question

Resources exposed (4)

URI	Payload
foldkit://spine	7-prime spine with glyphs + names + ISA-95 layer mapping
foldkit://kappa-bands	7-band κ definitions (bounds · glyph · ring · warn / orphan flags)
foldkit://ops	6 fold operations (kanji · arrow · verb · probe)
foldkit://constants	φ · κ · Ω · θ · θ_step · BASELINE

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Example prompts (once installed)

• "Fold the state [1,0,2,0,0,1,0] using foldkit."
• "What κ-band is this text in: 'I notice I'm feeling stuck'?"
• "Apply the fire op to ring 3 of the baseline state."
• "Read foldkit://spine and explain the ISA-95 mapping."

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Canonical -mcp companion shape

This repo is exemplar #2 (after fallreach-sdk). Every estate -mcp follows the same skeleton:

<name>-mcp/
├── src/
│   ├── server.js         · thin stdio server · < 100 lines
│   ├── tools.js          · TOOLS[] + callTool()
│   └── resources.js      · RESOURCES[] + readResource()
├── package.json          · bin: <name>-mcp → src/server.js
├── manifest.json         · MCP-side declarative index
├── README.md             · install snippets for all major clients
├── LICENSE               · MIT
└── .github/workflows/publish.yml   · npm publish on v* tag

Fork · rename · rewire tools/resources to the substrate you're exposing · ship.

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AI-Native Solutions · ai-nativesolutions.com