Check an x402 endpoint BEFORE paying it
Check an x402 endpoint BEFORE paying it. Makes one unpaid request (never sends money), decodes the 402 terms, and verifies: the asset is a real USD stablecoin on that network, the price in USD vs your max_price_usd cap (default $0.50), payTo is a sane address (and matches expected_pay_to if given), HTTPS and certificate validity, redirects, and domain age. Returns safe_to_pay, a risk level, findings, and the cheapest acceptable payment option.
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://agents.supremeai.ca/v1/preflight
| Category | Market data |
|---|---|
| Provider host | agents.supremeai.ca |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
We never call tools that send, buy, move money or file anything, not even without paying.
Example input (from the provider)
{
"body": {
"max_price_usd": 0.05,
"url": "https://agents.supremeai.ca/v1/validate"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"properties": {
"body": {
"description": "JSON body to send with POST probes",
"type": "object"
},
"expected_pay_to": {
"description": "wallet you expect to be paid",
"type": "string"
},
"max_price_usd": {
"description": "highest acceptable price, default 0.50",
"type": "number"
},
"method": {
"description": "GET or POST; default tries GET then POST",
"type": "string"
},
"url": {
"description": "x402 endpoint you intend to pay",
"type": "string"
}
},
"required": [
"url"
],
"type": "object"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"checks": {
"type": "object"
},
"findings": {
"type": "array"
},
"payment_options": {
"type": "array"
},
"recommended_option": {
"type": [
"integer",
"null"
]
},
"risk": {
"enum": [
"low",
"medium",
"high",
"unknown"
],
"type": "string"
},
"safe_to_pay": {
"type": [
"boolean",
"null"
]
},
"summary": {
"type": "string"
}
},
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}