curl --request POST \
  --url https://api.polyfeed.dev/v1/billing/x402/quote \
  --header 'Content-Type: application/json' \
  --data '
{
  "tierId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "network": "<string>",
  "tokenSymbol": "<string>"
}
'

{
  "provider": "x402",
  "challenge": {
    "accepts": [
      {
        "scheme": "exact",
        "network": "base-sepolia",
        "asset": "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
        "amount": "19900000",
        "payTo": "0x0000000000000000000000000000000000000000",
        "maxTimeoutSeconds": 300,
        "extra": {
          "name": "USDC",
          "version": "2"
        }
      }
    ],
    "tier_id": "27b20245-02d0-45b1-98a2-55263dc5c8ec"
  },
  "priceUsd": 19.9,
  "priceAmount": "19900000",
  "expiresAt": "2026-05-12T17:05:00.000Z"
}