Api Endpoint

SpendPreflight

Spend preflight for AI agents. Send the x402 PaymentRequired body (v1 or v2) you received, or a cart, plus optional rules (per-payment max, hold threshold, daily cap, allowlists, new-domain days, endpoint category price multiple, liveness and payTo changes). Returns allow|hold|block with reasons, the cheapest acceptable payment option, and a receipt id. Read-only: never signs, settles, or holds funds. Use before every payment.

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Offering

Provider
api.spendpreflight.com
Method
POST
Offering type
Api Endpoint
Transport type
http
Category
Blockchain And Crypto
Delivery
Not provided
Pricing model
Not provided
x402 version
2

Endpoint context

URL
https://api.spendpreflight.com/v1/preflight
MIME type
Not provided
First seen
2026-10-16T01:50:38.788Z
Last seen
Tags
agent-payments, X402, spend-control, preflight, budget

Payment pricing

x402 payment terms are the authoritative price for calling this endpoint.

Payment option 1
0.02 USDC
Atomic price: 20000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Raw x402 terms
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "20000",
    "payTo": "0xBf4164e07552e4c1b1B1597E72C7acAA3F0a1c58"
  }
]

Observed health

Status
Healthy
Latest latency
242 ms
Average latency
500 ms
HTTP status
204
Last checked
Reachability
100% over 14 checks

Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.

Input schema

{
  "additionalProperties": false,
  "properties": {
    "body": {
      "properties": {}
    },
    "bodyType": {
      "enum": [
        "json",
        "form-data",
        "text"
      ],
      "type": "string"
    },
    "method": {
      "enum": [
        "POST"
      ],
      "type": "string"
    },
    "type": {
      "const": "http",
      "type": "string"
    }
  },
  "required": [
    "type",
    "method",
    "bodyType",
    "body"
  ],
  "type": "object"
}

Output schema

{
  "properties": {
    "example": {
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}