Co-purchase for one seller over the indexed window: how many of its buyers also pay someon

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x790fE337b89900028E16fE63Cc087112F7a2BA49",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "50000",
    "maxTimeoutSeconds": 60
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "payTo": "DMrJUdvmorbEXx8pA4R8yZ9kPfH3pUanCGxoG5AoPuTC",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "50000",
    "maxTimeoutSeconds": 60
  }
]

{
  "bazaar": {
    "info": {
      "input": {
        "method": "GET",
        "queryParams": {
          "seller": "api.onesource.io"
        },
        "type": "http"
      },
      "output": {
        "example": {
          "as_of": "2026-09-01",
          "fact": {
            "buyers": 96,
            "co_sellers": [
              {
                "lift": 3.4,
                "seller": "0xcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcd",
                "shared_buyers": 21
              }
            ],
            "multi_seller_share": 0.4375
          },
          "frame": "settler-eip3009-base",
          "tier": "full"
        },
        "format": "application/json",
        "type": "json"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "additionalProperties": false,
          "properties": {
            "method": {
              "const": "GET",
              "type": "string"
            },
            "queryParams": {
              "additionalProperties": false,
              "properties": {
                "seller": {
                  "description": "the seller whose buyers are being looked up, as its payTo address or one of its hostnames",
                  "type": "string"
                }
              },
              "required": [
                "seller"
              ],
              "type": "object"
            },
            "type": {
              "const": "http",
              "type": "string"
            }
          },
          "required": [
            "type",
            "method",
            "queryParams"
          ],
          "type": "object"
        },
        "output": {
          "additionalProperties": false,
          "properties": {
            "example": {
              "description": "a worked response, shortened — the shape a full answer has",
              "type": "object"
            },
            "format": {
              "const": "application/json",
              "description": "the basket envelope: as_of, frame, coverage, method, attribution, tier, window_days and a fact carrying buyers, multi_seller_share and the top co-sellers with shared_buyers and lift",
              "type": "string"
            },
            "type": {
              "const": "json",
              "type": "string"
            }
          },
          "required": [
            "type",
            "format"
          ],
          "type": "object"
        }
      },
      "required": [
        "input"
      ],
      "type": "object"
    }
  }
}

curl "https://parallax402.com/v1/basket"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

const res = await fetch("https://parallax402.com/v1/basket");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

import httpx
res = httpx.get("https://parallax402.com/v1/basket")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header