fiatdock.com

Live 402 challenge

Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.

{
  "docs": "https://fiatdock.com/llms.txt",
  "hint": "This endpoint costs $0.0018 USDC per call via x402 on base. NOTHING was charged and nothing was created — a 402 is only the invoice, so retrying is always safe. To pay: sign the requirements in `accepts` (also base64-JSON in the PAYMENT-REQUIRED response header) and retry the SAME request with a PAYMENT-SIGNATURE header (the x402 v2 name; X-PAYMENT is accepted too). Easiest path: run `npx fiatdock-mcp` with AGENT_PRIVATE_KEY set to a Base wallet holding USDC — it signs and retries for you.",
  "error": "payment required",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2"
      },
      "payTo": "0xeB12bB2f52EeD33DBa6A00774E48324032Fd87C6",
      "amount": "1800",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 300
    }
  ],
  "howToPay": {
    "step1": "Sign an EIP-3009 transferWithAuthorization. The EIP-712 domain is {name, version} from `extra`, chainId from `network`, verifyingContract = `asset`. The message is the `authorization` object below.",
    "step2": "Fill in the placeholders below, then base64(JSON.stringify(envelope)).",
    "step3": "Send it as the PAYMENT-SIGNATURE request header (X-PAYMENT is also accepted) and retry the SAME request.",
    "noWallet": "No signer? `npx fiatdock-mcp` with AGENT_PRIVATE_KEY set to a Base wallet holding USDC signs and retries automatically.",
    "notCharged": "A 402 costs nothing — it is the price, not a bill. Retrying is always safe.",
    "payloadTemplate": {
      "scheme": "exact",
      "network": "eip155:8453",
      "payload": {
        "signature": "<0x + 130 hex: your EIP-712 signature>",
        "authorization": {
          "to": "0xeB12bB2f52EeD33DBa6A00774E48324032Fd87C6",
          "from": "<0x + your wallet address>",
          "nonce": "<0x + 64 hex: 32 random bytes, never reused>",
          "value": "1800",
          "validAfter": "0",
          "validBefore": "<unix seconds, e.g. now + 60>"
        }
      },
      "accepted": {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "payTo": "0xeB12bB2f52EeD33DBa6A00774E48324032Fd87C6",
        "amount": "1800",
        "scheme": "exact",
        "network": "eip155:8453",
        "maxTimeoutSeconds": 300
      },
      "x402Version": 2
    }
  },
  "priceUsd": 0.0018,
  "freeAlternative": "GET https://fiatdock.com/v1/token/price?symbol=ETH (free) and GET https://fiatdock.com/v1/quote (free)"
}

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": "0xeB12bB2f52EeD33DBa6A00774E48324032Fd87C6",
    "scheme": "exact",
    "network": "eip155:8453",
    "mimeType": "application/json",
    "resource": "https://fiatdock.com/v1/weather/forecast",
    "description": "",
    "maxAmountRequired": "1800",
    "maxTimeoutSeconds": 300
  }
]

Provenance

Seen in the source catalog

2026-10-12 13:31Z

Last indexed by Roundhouse

2026-10-19 18:15Z

Last enriched (probe, favicon, geo)

2026-10-15 15:15Z

x402 version

1

Max timeout

300s

Liveness probe

HTTP 402