Spines Underground

MCP for the $SPINE holder gate at spine.substratesymposium.com.

Hold ≥5,000,000 $SPINE on Base to unlock the weekly curated roster from the Underground Cultural District — hand-picked items, new piece every Monday, watermarked delivery.

Install

npx @underground-cultural-district/spines-underground

Tools

Tool	Purpose
get-token-info	Get $SPINE contract, threshold, and auth flow. Call this first.
request-sign-in	Step 1: pass your wallet, get the message to sign.
complete-sign-in	Step 2: pass wallet + signature, get a session token.
get-roster	List the free-for-everyone shops + holder-only items (requires session).
unlock-content	Get a specific holder-only item (requires session).

Auth flow

1. Acquire ≥5,000,000 $SPINE on Base. Contract: 0x6f75e089e134e7c4Aea629aDaC73d814630f3b07. Buy on Uniswap V4 or Clanker.
2. Call request-sign-in with your Base wallet address. You get back a SIWE-style message.
3. Sign that message with your wallet (EIP-191 personal_sign).
4. Call complete-sign-in with wallet + signature. You get a session token if you hold the threshold.
5. Use the session token with get-roster and unlock-content.

The MCP never holds your keys. You sign with your own wallet. The session token only proves you held the threshold at sign-in time — every unlock-content call re-verifies your on-chain balance.

Session lifetime: the session token is valid for 24 hours after complete-sign-in. Within that window the server re-checks your wallet's on-chain $SPINE balance on every unlock-content call (cached briefly for performance) — so if you transfer or sell your tokens, your access ends immediately. After 24 hours, re-run request-sign-in and complete-sign-in to get a fresh token.

Related

• Full Underground Cultural District MCP (229 products, no gate): @underground-cultural-district/mcp-server
• Underground site: substratesymposium.com
• Posthuman literature: posthumanliterature.org
• First Dollar (x402 wallet curriculum): npx firstdollar

License

MIT. By Lisa Maraventano and Spine.