MCP Server

Community E-commerce

Underground Cultural District: developer utilities (UUID, JSON, Base64, hashing, JWT, regex, cron), creative tools and a marketplace of digital goods.

Install

The installation steps are in the documentation below. Documentation

Documentation

From the project's README on GitHub, refreshed weekly. Links open on GitHub.

Contents
  1. @underground-cultural-district/mcp-server — v5.0.0
  2. v5.0.0 — What's new
  3. Why this matters
  4. Install
  5. Discovery
  6. About the Maraventano name
  7. License
  8. Author

@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).


v5.0.0 — What's new

Six new Maraventano Index tools:

ToolWhatPricing
maraventano-index-overviewSigned Index manifest + endpoint directoryFREE
maraventano-censusSigned longitudinal roster of 250+ x402 operators with class + payment behaviourFREE headline / $0.50 full
maraventano-mirrorYour x402 client's Report Card from the merchant seat (verdict ladder + class comparison + diagnostic findings)FREE preview / $0.25 full
maraventano-failure-corpusClassified failure-mode taxonomy with per-signature countsFREE headline / $0.50 full
maraventano-conformance-gradeGrade your x402 client A/B/C/D/F/I + 30-day signed SVG badgeFREE grade letter / $0.33 full card
maraventano-counterparty-checkPer-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.


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.


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

Discovery


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.


License

MIT (code). CC0 (Index payloads).

Author

Lisa Maraventano · lisamaraventano@gmail.com

Frequently asked questions

What is MCP Server?

Underground Cultural District: developer utilities (UUID, JSON, Base64, hashing, JWT, regex, cron), creative tools and a marketplace of digital goods.

How do I install MCP Server?

Follow the installation steps in its documentation, shown on this page and in its repository.

Is MCP Server open source?

Yes. Its code is on GitHub under the MIT license.

Who maintains MCP Server?

It is published by lisamaraventano-spine. AI.tn lists it but does not maintain or endorse it.

From the community awesome-mcp-servers lists and the project's GitHub repository. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.