x402station.io API reference

Preflight endpoint risk check

Synchronous risk check before an agent pays an unfamiliar x402 endpoint.

This HTML page is served by GET /api/v1/preflight. The paid API operation remains POST /api/v1/preflight.

Signature
POST /api/v1/preflight

Pricing
$0.001 USDC or X-Credit-Id

Settlement
x402 v2 · exact · Base mainnet USDC

Canonical
https://x402station.io/api/v1/preflight

x402 challenge example

HTTP/1.1 402 Payment Required
payment-required: <base64 PaymentRequiredResponse>
www-authenticate: x402
content-type: application/json; charset=utf-8

{
  "x402Version": 2,
  "error": "Payment required",
  "resource": {
    "url": "https://x402station.io/api/v1/preflight",
    "description": "Preflight endpoint risk check"
  },
  "accepts": [
    {
      "scheme": "exact",
      "network": "eip155:8453",
      "asset": "USDC",
      "amount": "1000",
      "payTo": "0x4053338C7cB38624C0bc23c900F78Cf8470b4E38",
      "maxTimeoutSeconds": 300
    }
  ]
}

Request body

{
  "url": "https://api.example.com/x402-endpoint"
}

Success response

{
  "ok": true,
  "warnings": [],
  "metadata": {
    "service_id": "svc_example",
    "price": {
      "amount": "0.005",
      "currency": "USDC",
      "network": "Base"
    },
    "uptime_pct_1h": 100,
    "established": true
  },
  "risk_score": 8,
  "confidence": 0.86,
  "recommended_action": "pay"
}

Error codes

status	meaning
`400`	Malformed JSON body, invalid URL, or missing required field.
`402`	Payment required. Decode payment-required, sign x402, retry.
`503`	Query/probe pipeline timeout. Treat as failed preflight; do not pay target blindly.
`422`	Target URL is syntactically valid but not processable as an x402 endpoint.

Notes