One-call Base (8453) preflight
One-call Base (8453) preflight: risk snapshot + live ERC-20 approvals + OFAC SDN screen + optional x402 invoice check (?invoice= JSON or base64). Returns risk, approvals, invoice, sanctions and summary {verdict proceed|review|stop, flags}. Free sample: /api/preflight/sample. 400 bad input; 503 not charged. Informational, not a guarantee.
Answeringour last check, 2026-10-25
1 of 1checks answered this week
254 msmedian answer time
$0.05listed price per call
$0.05price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
GET https://x402-research-iota.vercel.app/api/x402/preflight
| Category | Company and compliance |
|---|---|
| Provider host | x402-research-iota.vercel.app |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-25 | valid payment request | 402 | $0.05 | 254 ms |
Example input (from the provider)
{
"method": "GET",
"queryParams": {
"address": "0xf9623fab6780984eacac443158c0309519451afa"
},
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"properties": {
"address": {
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"invoice": {
"description": "optional x402 PaymentRequired, raw JSON or base64",
"type": "string"
}
},
"required": [
"address"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"address": {
"type": "string"
},
"approvals": {
"type": "object"
},
"invoice": {
"type": [
"object",
"null"
]
},
"risk": {
"type": "object"
},
"signed": {
"type": "boolean"
},
"summary": {
"properties": {
"coverageNote": {
"type": "string"
},
"flags": {
"items": {
"type": "object"
},
"type": "array"
},
"highRiskCount": {
"type": "number"
}
},
"type": "object"
}
},
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}