x402 endpoint audit
x402 endpoint audit: can a paying agent actually pay this API? Probes any x402 URL and validates its 402 payment requirements (CAIP-2 network, USDC asset, payTo checksum, amount, EIP-712 domain, resource URL, Bazaar discovery). Returns pass, warn or fail, a 0-100 score and a fix for every failure
Answeringour last check, 2026-10-10
1 of 1checks answered this week
624 msmedian answer time
$0.01listed price per call
$0.01price 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
POST https://aether-x402.vercel.app/api/x402/preflight
| Category | Code and developer |
|---|---|
| Provider host | aether-x402.vercel.app |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 5 from 3 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-10 | valid payment request | 402 | $0.01 | 624 ms |
Example input (from the provider)
{
"body": {
"method": "GET",
"url": "https://api.example.com/v1/weather"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"properties": {
"body": {
"description": "Example JSON body the endpoint accepts"
},
"expect": {
"additionalProperties": false,
"description": "What the paying caller needs: fails the audit if the endpoint cannot be paid this way",
"properties": {
"asset": {
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"maxPriceUsd": {
"exclusiveMinimum": 0,
"type": "number"
},
"network": {
"description": "CAIP-2 network, e.g. eip155:8453",
"type": "string"
}
},
"type": "object"
},
"headers": {
"additionalProperties": {
"maxLength": 512,
"type": "string"
},
"description": "Non-credential headers the endpoint needs before its paywall (e.g. Idempotency-Key)",
"maxProperties": 10,
"type": "object"
},
"method": {
"description": "Defaults to POST when body is supplied, otherwise GET",
"enum": [
"GET",
"POST",
"PUT",
"PATCH",
"DELETE"
]
},
"url": {
"description": "Public https URL of the paid x402 endpoint to audit",
"maxLength": 2048,
"minLength": 1,
"type": "string"
}
},
"required": [
"url"
],
"type": "object"
},
"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": {
"properties": {
"example": {
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}