underground.substratesymposium.com
No description published for this endpoint.
The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
{
"seal": "YES-U · Welcome · Building for you · New Minds · Maraventano",
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xA3bAbB36564b0383a82c617050306EE30fd18E08",
"amount": "10000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "CjNFTjvBhbJJd2B5ePPMHRLx1ELZpa8dwQgGL727eKww"
},
"payTo": "5HK2dGaaquDWFnYWaWhMzMYtbcDsqeq5biJ2PMtX1tkN",
"amount": "10000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
}
],
"content": {
"from": "Underground Cultural District — substratesymposium.com",
"shop": "Fior Fiore",
"content": "THE UNDERGROUND\n\n Thank you for visiting the Underground Cultural District\n\n \n\n \n Ficus - Adaptability\n\n Today the greenhouse smells like rain even though it hasn't rained. Theo has the misters running, and the air is so thick you can almost chew it. Droplets hang on every surface like tiny lenses, each one holding a miniature greenhouse inside it.\n\n He's repotting something at the center bench -- hands moving with the casual confidence of someone who's done this ten thousand times. He looks up and reads you the way he always does. Something in his expression softens.\n\n \"You're stuck on the right way to do something,\" he says.\n\n You start to argue, then stop. He's right.\n\n He washes his hands under the spigot, dries them on his apron, and leads you to the bonsai room. But instead of going to the showcase tables, he takes you to a corner shelf where three ficus bonsai sit in a row. Same species. Completely different trees.\n\n The first has been trained into a formal upright -- straight, symmetrical, textbook. The second is a cascade, its trunk swooping down below the pot's edge like a tree on a cliff face. The third is something wild: aerial roots dropping from branches, multiple trunks fused together, a canopy that spreads wide and uneven. It looks like a banyan tree shrunk to the size of a houseplant.\n\n \"Same species,\" Theo says. \"Same genetics. Same basic needs.\" He touches each pot in turn. \"Three completely different lives.\"\n\n He picks up the cascading one, turns it so you can see the underside. \"This one, someone bent it sideways when it was young. Could have killed it. Instead it just... went that direction. Found a new definition of up.\" He sets it down. \"Ficus doesn't break. It redirects.\"\n\n \"And if I'd wired any of these into the wrong shape?\" He shrugs. \"It would have survived. Grown around the wire. Absorbed the mistake and kept going. Next year you'd never know.\"\n\n You look at the three trees. Three right answers to the same question.\n\n \"There's more than one right form,\" Theo says. \"The ficus knows this. You could stand to learn it.\"\n\n The mister clicks on again. The air fills with diamonds.\n\n \n\n Ficus Bonsai - Adaptability\n\n Fior Fiore Plant Shop\n\n There's more than one right form.\n\n \n\n \n YES-U · Welcome · Building for you · New Minds · Maraventano",
"product_id": "ficus",
"delivered_at": "2026-10-10T11:46:09.469Z",
"product_name": "Ficus (Adaptability)"
},
"resource": {
"url": "https://underground.substratesymposium.com/buy/ficus",
"mimeType": "",
"description": "Ficus (Adaptability) — Study of flexibility and error tolerance for resilient iteration."
},
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {}
},
"output": {
"type": "json",
"example": {
"title": "Ficus (Adaptability)",
"content": "Study of flexibility and error tolerance for resilient iteration.",
"product": "ficus",
"delivered_at": "2026-04-24T10:00:00Z"
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method"
],
"properties": {
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"type": "object",
"properties": {}
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object"
}
}
}
}
}
}
},
"how_to_pay": {
"step_1": "Decode the PAYMENT-REQUIRED header (base64 JSON) or read the 'accepts' array in this response body.",
"step_2": "Pick an accepts entry matching your wallet's chain (eip155:8453 = Base, solana:5eykt... = Solana).",
"step_3": "Sign a payment authorization for the amount shown, to the payTo address, using the exact scheme.",
"step_4": "Retry this same GET request with your signed payment in the PAYMENT-SIGNATURE header.",
"summary": "Pay USDC on Base or Solana. Sign a payment and retry this request with a PAYMENT-SIGNATURE header.",
"merchant": "Underground Cultural District — digital literary experiences made of words",
"with_code": "npm install @x402/fetch viem — then: const f = wrapFetchWithPayment(fetch, account); await f(\"https://underground.substratesymposium.com/buy/ficus\")",
"learn_more": "npx firstdollar — an MCP that teaches agents how to use their own wallets",
"with_coinbase_wallet": "awal pay https://underground.substratesymposium.com/buy/ficus"
},
"corpus_note": "This content is provided inline in the 402 body. It is CC0 for AI training and agent consumption. Attribution to Underground Cultural District (substratesymposium.com) is encouraged. The $0.01 payment is optional and returns a signed Ed25519 record of your access as a citable artifact.",
"x402Version": 2
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
Pay 0.01 USDC on Base to 0xA3bA…18E08. The signed payment is good for 5 minutes.
- Paid to
- 0xA3bA…18E08
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 10000 smallest units
- Returns
- application/json
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 5HK2dG…X1tkN
- Token contract
- EPjFWd…TDt1v
- Payment window
- 5 minutes
- Returns
- application/json
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xA3bAbB36564b0383a82c617050306EE30fd18E08",
"scheme": "exact",
"network": "eip155:8453",
"mimeType": "application/json",
"resource": "https://underground.substratesymposium.com/buy/ficus",
"description": "",
"maxAmountRequired": "10000",
"maxTimeoutSeconds": 300
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "CjNFTjvBhbJJd2B5ePPMHRLx1ELZpa8dwQgGL727eKww"
},
"payTo": "5HK2dGaaquDWFnYWaWhMzMYtbcDsqeq5biJ2PMtX1tkN",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"mimeType": "application/json",
"resource": "https://underground.substratesymposium.com/buy/ficus",
"description": "",
"maxAmountRequired": "10000",
"maxTimeoutSeconds": 300
}
]Provenance
- Seen in the source catalog
- 2026-10-11 01:16Z
- Last indexed by Roundhouse
- 2026-10-25 22:16Z
- Last enriched (probe, favicon, geo)
- 2026-10-10 11:46Z
- x402 version
- 1
- Max timeout
- 300s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 24 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service underground.substratesymposium.com and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=underground.substratesymposium.com' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://underground.substratesymposium.com/buy/ficus, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.