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underindex

underindex

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github.com/ascanioUnderIndexGames & Entertainment0Updated 1d ago
Repository

About underindex

underindex provides Claude and other MCP clients with verified records on 60 niche fashion subcultures, covering dates, brands, iconic items, music, places to buy, and price ranges. Its three tools include a daily free allowance for record lookups, with further access payable in USDC on Base.

Key features

  1. 01List subculture names and years
  2. 02Retrieve a complete sample record
  3. 03Look up verified subculture records
  4. 04Show brands, items, and price ranges
  5. 05Flag commonly confused subjects

Use cases

  1. 01Learn about iconic items in a fashion subculture
  2. 02Find related brands and places to buy
  3. 03Distinguish between similar subcultures
  4. 04Check a style's years and music context

MCP support

The MCP server offers tools to list subcultures, retrieve a sample, and look up individual records. Record lookups include three free per day; with a wallet configured, additional requests are paid automatically in USDC on Base through x402.

Configuration

Local server config is the same for every client. Copy it into your client’s MCP config file.

mcp.json · Universal config
{
  "mcpServers": {
    "ascaniounderindex-underindex": {
      "command": "npx",
      "args": [
        "-y",
        "underindex-mcp"
      ],
      "env": {
        "UNDERINDEX_PRIVATE_KEY": "<UNDERINDEX_PRIVATE_KEY>",
        "UNDERINDEX_MAX_PER_CALL": "<UNDERINDEX_MAX_PER_CALL>"
      }
    }
  }
}
Run commandnpx -y underindex-mcp
Environment variables to set
UNDERINDEX_PRIVATE_KEYSecretPrivate key of a dedicated EVM wallet holding USDC on Base. Optional: without it get_subculture uses the free allowance of 3 records a day.
UNDERINDEX_MAX_PER_CALLHard spending cap per lookup, default $0.05

Local servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.

Packages
npmunderindex-mcp0.2.0

Tools

3

Saved tool list · updated 1w ago

This tool takes no parameters.

Details

From the project README

UnderIndex MCP server

Listed on mcpservers.org

Gives Claude (or any MCP client) verified records on 60 niche fashion subcultures: years, key brands, iconic items, music, where to buy, a price range, and a WARNING note on what each one must not be confused with. It is the UnderIndex API as three tools.

ToolCostWhat it does
list_subculturesfreeEvery slug with its name and years
get_sample_recordfreeOne complete record (Goth Ninja), to see the shape
get_subculture3 free a day, then $0.01 USDC on BaseOne record, paid automatically over x402

Without a wallet key get_subculture uses the free allowance: 3 records a day, resetting at midnight UTC. After that it explains how to enable payments. With a key set, every lookup is paid.

Install

Requires Node.js 20 or later. Nothing to download: npx fetches the underindex-mcp package on first run.

Claude Desktop

Add this to claude_desktop_config.json (Settings → Developer → Edit Config):

{
  "mcpServers": {
    "underindex": {
      "command": "npx",
      "args": ["-y", "underindex-mcp"],
      "env": {
        "UNDERINDEX_PRIVATE_KEY": "0x..."
      }
    }
  }
}
Claude Code
claude mcp add underindex -e UNDERINDEX_PRIVATE_KEY=0x... -- npx -y underindex-mcp

Leave out UNDERINDEX_PRIVATE_KEY to use only the free tools.

Configuration

VariableDefaultNotes
UNDERINDEX_PRIVATE_KEYnonePrivate key of an EVM wallet holding USDC on Base. Use a dedicated wallet with a few dollars in it, never your main one.
UNDERINDEX_MAX_PER_CALL$0.05Hard cap per lookup. The server refuses to pay more than this, whatever the API asks.
UNDERINDEX_API_URLhttps://underindex-api.onrender.comPoint it at a self-hosted server, e.g. one running on Base Sepolia testnet.

An unknown slug returns 404 before any payment is requested, so typos cost nothing. Each paid answer ends with a link to the payment on BaseScan.

Try it for free

The API's own server starts on Base Sepolia testnet when self-hosted, where test USDC is free from a faucet. Run it as described in the main README, then set UNDERINDEX_API_URL=http://localhost:3000 and a testnet wallet key.

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