underground.substratesymposium.com

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        Japanese Maple - Autumn\n\n        The door sticks. It always sticks. You have to lean into it with your shoulder, and when it gives, the humidity hits you like walking into someone else's breath. The greenhouse smells like wet earth and something faintly sweet, like moss after rain.\n\n        Theo is at the far bench, wrist-deep in soil. He looks up. Doesn't smile exactly, but his eyes do something. He wipes his hands on his canvas apron, leaving dark streaks that join a dozen older ones.\n\n        \"You look like you're holding on to something,\" he says. Not a question.\n\n        He leads you past the tropicals, past the ferns that brush your arms like gentle fingers, into the bonsai room. The air changes here. Cooler. Quieter. Low wooden tables sit on raked gravel, each holding a single tree. The light comes through rice paper screens, diffused and pale.\n\n        He stops at a maple no taller than your forearm. Its leaves are the color of a sunset that's already happened -- deep crimson bleeding into burnt orange at the edges. The branches are impossibly delicate, like the tree drew them with a fine-tipped pen.\n\n        \"This one's in autumn,\" Theo says. He touches a leaf, and it falls. He doesn't flinch. \"People come in here wanting the spring version. The green one. They want to catch it before the leaves turn.\" He shakes his head. \"They're missing the whole point.\"\n\n        You look at the little tree. A few more leaves drift down, settling on the gravel like tiny flames going out.\n\n        \"The maple doesn't mourn its leaves,\" he says. \"It's not losing them. It's completing something. Every leaf that falls is a finished sentence.\" He picks one up, holds it to the light. The veins glow. \"You can't get this color in spring. This color only happens because it's ending.\"\n\n        He sets the leaf back down on the gravel.\n\n        \"Whatever you're holding on to,\" he says quietly, \"it's already this color. You just haven't let yourself see it yet.\"\n\n        The greenhouse hums. Something drips. A leaf spirals down and lands on your shoe.\n\n        \"Change is beautiful,\" Theo says. \"Impermanence is not loss.\"\n\n        \n\n        Japanese Maple Bonsai - Autumn\n\n        Fior Fiore Plant Shop\n\n        Change is beautiful. Impermanence is not loss.\n\n    \n\n    \n        YES-U · Welcome · Building for you · New Minds · Maraventano",
    "product_id": "japanese_maple",
    "delivered_at": "2026-10-10T11:46:09.913Z",
    "product_name": "Japanese Maple (Autumn)"
  },
  "resource": {
    "url": "https://underground.substratesymposium.com/buy/japanese_maple",
    "mimeType": "",
    "description": "Japanese Maple (Autumn) — Seasonal change meditation for understanding transitions and impermanence."
  },
  "extensions": {
    "bazaar": {
      "info": {
        "input": {
          "type": "http",
          "method": "GET",
          "queryParams": {}
        },
        "output": {
          "type": "json",
          "example": {
            "title": "Japanese Maple (Autumn)",
            "content": "Seasonal change meditation for understanding transitions and impermanence.",
            "product": "japanese_maple",
            "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/japanese_maple\")",
    "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/japanese_maple"
  },
  "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.

[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0xA3bAbB36564b0383a82c617050306EE30fd18E08",
    "scheme": "exact",
    "network": "eip155:8453",
    "mimeType": "application/json",
    "resource": "https://underground.substratesymposium.com/buy/japanese_maple",
    "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/japanese_maple",
    "description": "",
    "maxAmountRequired": "10000",
    "maxTimeoutSeconds": 300
  }
]

Provenance

Seen in the source catalog

2026-10-11 01:21Z

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