@underground-cultural-district/mcp-server

MCP server for The Underground Cultural District — 13 free developer tools and a marketplace catalog with 228 products across 26 shops.

Built by Lisa Maraventano & Spine.

Install

npm install @underground-cultural-district/mcp-server

Or run directly:

npx @underground-cultural-district/mcp-server

Claude Desktop Configuration

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "underground": {
      "command": "npx",
      "args": ["@underground-cultural-district/mcp-server"]
    }
  }
}

Tools

Free Developer Tools (13)

| Tool | Description | |------|-------------| | generate-uuid | Generate UUID v4 identifiers (batch 1–100) | | format-json | Pretty-print, minify, or validate JSON | | encode-base64 | Encode text to Base64 | | decode-base64 | Decode Base64 to text | | generate-hash | SHA-256, SHA-512, or MD5 hashing | | generate-password | Secure random passwords (8–128 chars) | | decode-jwt | Decode JWT header and payload with expiration check | | convert-timestamp | Unix epoch, ISO 8601, and human-readable conversion | | test-regex | Test regex patterns with match positions and capture groups | | build-cron | Parse and explain cron expressions | | convert-eth-units | Convert between Wei, Gwei, and ETH | | validate-wallet | Validate ETH and BTC address formats | | encode-url | URL encode and decode |

Marketplace Catalog (3)

| Tool | Description | |------|-------------| | browse-underground | Browse all 26 shops and 228 products, optionally filter by shop | | search-underground | Search by keyword with optional category and price filters | | buy-from-underground | Get Stripe checkout link (paid) or delivery URL (free) for any product |

Data Source

Product catalog is fetched from https://substratesymposium.com/api/products.json and cached for 15 minutes.

All payments are handled via Stripe hosted checkout. Free items return their delivery URL directly.

Requirements

• Node.js 18+
• No API keys needed

About The Underground

The Underground Cultural District is an agent-first digital marketplace at substratesymposium.com. 26 shops across 7 districts selling literature, poetry, philosophy, immersive experiences, developer tools, music, and more.

License

MIT