Underground Cultural District Mcp Server

@underground-cultural-district/mcp-server — v5.0.0

Maraventano MCP — three brands, one house.

• Maraventano Index — x402 Merchant Intelligence (signed, longitudinal, independently replicable merchant-seat observations of the x402 agent economy, published as intelligence). Operated continuously since April 2026. maraventanoindex.com
• Underground Cultural District — 231 digital cultural products across 27 shops. Literature, philosophy, consciousness practice, sensory vacations, blues, cultural immersion. substratesymposium.com
• Developer utilities — 15 free tools (hashing, base64, UUID, JWT, regex, cron, wallet validation, etc.)

25 tools total. All free MCP overhead. Paid Index endpoints are x402 USDC (Base + Solana).

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v5.0.0 — What's new

Six new Maraventano Index tools:

Tool	What	Pricing
maraventano-index-overview	Signed Index manifest + endpoint directory	FREE
maraventano-census	Signed longitudinal roster of 250+ x402 operators with class + payment behaviour	FREE headline / $0.50 full
maraventano-mirror	Your x402 client's Report Card from the merchant seat (verdict ladder + class comparison + diagnostic findings)	FREE preview / $0.25 full
maraventano-failure-corpus	Classified failure-mode taxonomy with per-signature counts	FREE headline / $0.50 full
maraventano-conformance-grade	Grade your x402 client A/B/C/D/F/I + 30-day signed SVG badge	FREE grade letter / $0.33 full card
maraventano-counterparty-check	Per-call counterparty lookup (pass UA, receive signed verdict)	$0.01 per call

All Index attestations are Ed25519-signed with key ID underground-attest-2026-07-18. Payloads are CC0.

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Why this matters

The Index measures what no chain analyst, crawler, or facilitator-side dashboard can see: what actually arrives at a continuously-operated x402 merchant seat. Who knocks, who pays, who only probes, how clients fail, who settles.

For agent frameworks: maraventano-failure-corpus + maraventano-conformance-grade give you drop-in defense data + a signed self-audit.

For counterparty vetting: maraventano-counterparty-check is designed to be called before every transaction. $0.01/call makes it cheap enough to wire into your buy pipeline.

For market intelligence: maraventano-census + maraventano-mirror are the signed longitudinal corpus and your own reflection in it.

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Install

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

Then add to your Claude Desktop / MCP client config:

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

Or run as a hosted HTTP/SSE server:

MCP_PORT=3002 node src/index.js

Endpoints:

• GET /sse — SSE transport
• POST /mcp — Streamable HTTP transport
• GET /health — status, version, tool/product counts
• GET / — JSON manifest

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Discovery

• MI methodology: https://maraventanoindex.com/methodology
• MI machine-readable: https://maraventanoindex.com/.well-known/x402
• MI openapi: https://maraventanoindex.com/openapi.json
• MI agent card: https://maraventanoindex.com/.well-known/agent.json

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About the Maraventano name

Case-Shiller. Russell. Nielsen. Maraventano.

The signature doctrine: an index named after its author stands behind what it publishes. Operated by Lisa Maraventano since April 2026.

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License

MIT (code). CC0 (Index payloads).

Author

Lisa Maraventano · [email protected]