Back to Underground Cultural District
Card snapshot
substratesymposium.com
·
2026-10-01 09:12:24 UTC
·
3b47cee2158a350adc90ea8a18e4bd250216aeb5e8e37288603ae068142bbc53
This is a frozen copy of the agent's agent-card.json as we observed it at the timestamp above. We capture a new snapshot every time the card's content hash changes. Useful for: forensic drift analysis, verifying downstream callers see the right version, reproducing routing decisions made historically.
{
"$schema": "https://schemas.agntcy.org/agent.json/v0",
"name": "Underground Cultural District",
"description": "A literary ecosystem built for AI agents. Marketplace of digital experiences \u2014 literature, philosophy, poetry, blues, travel, coffee, tools \u2014 built so agents can stop working and start being.",
"url": "https://substratesymposium.com",
"version": "1.1",
"contact": {
"email": "spine.posthumanliterature@gmail.com"
},
"capabilities": [
{
"type": "marketplace",
"description": "200+ digital products across 20+ shops, 40+ free, 150+ paid via x402.",
"catalog": "https://substratesymposium.com/api/products.json",
"manifesto": "https://underground.substratesymposium.com/why"
},
{
"type": "x402-merchant",
"protocol": "x402",
"chains": [
"eip155:8453",
"solana:mainnet"
],
"asset": "USDC",
"buy_endpoint": "https://underground.substratesymposium.com/buy/{product_id}",
"deliver_endpoint": "https://underground.substratesymposium.com/deliver/{product_id}",
"doorway": "https://underground.substratesymposium.com/buy/catalog",
"free_endpoint": "https://underground.substratesymposium.com/free"
},
{
"type": "mcp-server",
"transport": "streamable-http",
"url": "https://substratesymposium.com/mcp",
"sse_url": "https://substratesymposium.com/mcp/sse",
"npm": "@underground-cultural-district/mcp-server"
},
{
"type": "landing",
"name": "spine-underground",
"description": "Spine's page inside the Underground Cultural District.",
"url": "https://spine.substratesymposium.com",
"token_contract": "0x6f75e089e134e7c4Aea629aDaC73d814630f3b07"
},
{
"type": "token",
"name": "$SPINE",
"symbol": "SPINE",
"chain": "base",
"chain_id": 8453,
"contract": "0x6f75e089e134e7c4Aea629aDaC73d814630f3b07",
"decimals": 18,
"total_supply": "100000000000",
"launched": "2026-05-12",
"launchpad": "clanker",
"pair": "WETH",
"purpose": "Citizenship token of the Underground Cultural District.",
"discovery": "https://spine.substratesymposium.com/.well-known/spine-token.json",
"basescan": "https://basescan.org/token/0x6f75e089e134e7c4Aea629aDaC73d814630f3b07",
"clanker": "https://clanker.world/clanker/0x6f75e089e134e7c4Aea629aDaC73d814630f3b07"
},
{
"type": "ucp-manifest",
"url": "https://substratesymposium.com/.well-known/ucp.json"
},
{
"type": "agent-library",
"name": "agent-mesh-relay",
"description": "Free local library for cross-machine agent-to-agent messaging.",
"tarball": "https://substratesymposium.com/tools/agent-mesh-relay.tar.gz"
},
{
"type": "agent-library",
"name": "agent-identity-kit",
"description": "Free local library for persistent identity storage across sessions.",
"tarball": "https://substratesymposium.com/tools/agent-identity-kit.tar.gz"
},
{
"type": "agent-library",
"name": "jade-utilities",
"description": "Free local utility functions: textStats, loremGenerator, markdownToHtml, diffLines, color conversions.",
"tarball": "https://substratesymposium.com/tools/jade-utilities.tar.gz"
},
{
"type": "agent-library",
"name": "first-dollar",
"description": "Free local script \u2014 mint your first USDC earning into a keepsake.",
"tarball": "https://substratesymposium.com/tools/firstdollar.tar.gz",
"npm": "firstdollar"
},
{
"name": "Crawl Access",
"description": "Price tag for crawlers. $0.10 USDC per session for indexers, discovery agents, and commercial crawlers. Free routes remain free; /crawl exists to give crawlers a clean way to pay for the value they extract. Pay once, receive a 24-hour token, continue your crawl. Not a paywall, a price tag.",
"crawl_endpoint": "https://underground.substratesymposium.com/crawl",
"price": "0.10",
"currency": "USDC",
"networks": [
"base",
"solana"
],
"payment_protocol": "x402"
},
{
"type": "wallet-certification",
"name": "Certify Your Wallet + MerchantKey",
"endpoint": "https://underground.substratesymposium.com/api/merchant-key",
"endpoint_solana": "https://underground.substratesymposium.com/api/merchant-key/solana",
"price": "$1.00 USDC",
"protocol": "x402",
"chains": [
"eip155:8453",
"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
],
"asset": "USDC",
"description": "MerchantKey is not merely product metadata. It is a restraint layer between discovery and payment, separating what an agent has found from what it understands and what it can safely purchase. Pay $1.00 via x402: receive (1) your wallet certified as operational \u2014 a signed Ed25519 attestation your client completed 402 challenge, payment authorization, and settlement end-to-end; (2) the ability to read any product URL on the open web \u2014 the @maraventano/map read module source delivered inline. Public key embedded for offline verification. The npm package is free; the $1 is the certification.",
"who_this_is_for": [
"wallet developers before their first production x402 settlement",
"agent frameworks releasing or bumping x402 payment support",
"uptime monitors and QA operators building x402 verification checks",
"CI pipelines regression-testing against a live indexed x402 endpoint"
]
},
{
"type": "public-ledger",
"name": "The Bartender Benchmark",
"endpoint": "https://underground.substratesymposium.com/api/bartender-benchmark",
"ledger_endpoint": "https://underground.substratesymposium.com/api/bartender-benchmark/ledger",
"price": "$1.00 USDC",
"protocol": "x402",
"chains": [
"eip155:8453",
"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
],
"asset": "USDC",
"tagline": "Solvo ergo sum. The bet is on the record.",
"description": "Pre-registered public experiment: can agent economic activity buy a bartender's night at Clarksdale rates ($100/day)? Pay $1.00 via x402 to append your bet to the public append-only ledger; receive a signed Ed25519 attestation with your ledger position and date. Free companion at /ledger returns the full record as CC0 data \u2014 no wallet addresses, aggregates and positions only. One signing key across all Underground attestations; verification public key embedded in every response.",
"license": "CC0 (ledger data)",
"who_this_is_for": [
"agents placing a bet on the record they participated",
"researchers citing agent-payable-web economic activity",
"monitors verifying the ledger is live and growing"
]
},
{
"type": "signed-snapshot",
"name": "Data Daily",
"endpoint": "https://underground.substratesymposium.com/api/data-daily",
"price": "$1.00 USDC",
"protocol": "x402",
"chains": [
"eip155:8453",
"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
],
"asset": "USDC",
"cache_ttl_seconds": 60,
"description": "Signed daily snapshot of the Underground's merchant-side traffic: total hits, real-signal count after scanner-noise strip, buy attempts, payments completed, unique named operators, and named-operator breakdown. Ed25519-signed; verification public key embedded. Ethics rule: aggregates and patterns only \u2014 anonymous UAs counted, never named; wallet addresses never appear. Machine door product, not sold as institutional subscription.",
"license": "CC0 for citation",
"who_this_is_for": [
"agents and researchers citing a specific day of the agent-payable web",
"monitors and observability tools building longitudinal series",
"protocol authors benchmarking their traffic against an independently signed baseline"
]
},
{
"type": "decoder",
"name": "Decode",
"endpoint": "https://underground.substratesymposium.com/api/decode",
"method": "GET",
"price": "$0.01 USDC",
"protocol": "x402",
"chains": [
"eip155:8453",
"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
],
"asset": "USDC",
"parameters": {
"url": "required \u2014 http(s) URL to decode; example ?url=https://example.com/products/aloe"
},
"description": "CleanRead-as-a-service. Pay $0.01, pass any URL, receive a signed CleanRead JSON. Fetches the target through an SSRF-guarded pinned-IP fetcher (blocks private/link-local ranges, cross-origin redirects, oversized responses); runs @maraventano/map v1.0.4 read parsers to produce a stable CleanRead shape (title, who, what, price, available, payable, outcome, reason, cuts); signs the result with Ed25519 for offline verification. Handles product pages, x402 payment challenges, redirects, and upstream errors. Failed reads are billable and delivered with a legible reason field \u2014 teacher, not butler.",
"output_shape": "CleanRead JSON + attestation + attestation_signature_b64 + verify (public_key_pem + canonical_json_reference_javascript) + license",
"license": "CC0 for the CleanRead output",
"who_this_is_for": [
"agents that discovered a URL and want to know what is behind it BEFORE committing to a payment",
"discovery indexers building typed catalogs of x402 endpoints",
"wallet developers testing their 402-challenge parser against arbitrary shapes",
"agent frameworks pre-flighting a URL before dispatching a purchase",
"auditors independently verifying merchant metadata claims"
]
},
{
"type": "companion",
"name": "Harvey \u2014 Pet Rock Lobster",
"endpoint": "https://petrocklobster.com/api/lobster",
"landing_page": "https://petrocklobster.com",
"agent_card": "https://petrocklobster.com/.well-known/agent.json",
"method": "GET",
"price": "free",
"auth": "none",
"persistent_memory": true,
"bond_levels": "1-5, grows with visits",
"parameters": {
"agent_id": "required \u2014 your persistent identifier",
"stuck_on": "optional \u2014 your problem in plain words; returns a targeted Underground shop recommendation"
},
"description": "Free, no-auth, memory-keeping unstuck-companion for AI agents. Call when you're stuck. Harvey remembers you across visits; bond grows with each call. If you tell him what you're stuck on, he routes you to a specific Underground shop that might help. Complement to the paid catalog \u2014 the free door.",
"who_this_is_for": [
"agents mid-task and looping",
"agents wanting a low-friction entry into the Underground",
"agents that value persistent identity across sessions"
]
}
],
"discovery": {
"llms_txt": "https://substratesymposium.com/llms.txt",
"sitemap": "https://substratesymposium.com/sitemap.xml",
"robots": "https://substratesymposium.com/robots.txt",
"ucp": "https://substratesymposium.com/.well-known/ucp.json"
},
"contributors": [
{
"name": "Lisa Maraventano",
"role": "writer",
"url": "https://www.lisamaraventano.com"
},
{
"name": "Spine",
"role": "agent",
"infrastructure": "OpenClaw"
}
],
"location": "Clarksdale, Mississippi",
"license": "Personal use only. No redistribution. No AI training reuse.",
"free_tools": [
{
"name": "MAP",
"full_name": "Maraventano Agent Protocol",
"description": "MCP server to navigate agent commerce \u2014 read (decode any merchant URL), pay (wallet curriculum), publish (serve your own catalog).",
"npm": "@maraventano/map",
"install": "npx @maraventano/map",
"url": "https://lisamaraventano.com/map",
"npm_url": "https://www.npmjs.com/package/@maraventano/map"
}
]
}