x402 Offer Check API
x402 Offer Check API: probes a public x402 storefront from the Cloudflare edge (GET, POST, OPTIONS) and reports what a buyer sees - payment-required header vs body, extra, bazaar, CORS, header size, 404 on the other method - as findings by severity. $0.01 USDC per check, a live measurement (a replayed payment header returns the receipt, not a new measurement). POST JSON {url, method?}; free example at https://api.aiskills402.com/v1/run/x402-offer-check/example
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://api.aiskills402.com/v1/run/x402-offer-check
| Category | Everything else |
|---|---|
| Provider host | api.aiskills402.com |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 3 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-18 | valid payment request | 402 | $0.01 | 26 ms |
Example input (from the provider)
{
"body": {
"method": "auto",
"url": "https://api.aiskills402.com/v1/run/jsonl-repair"
},
"bodyType": "json",
"headers": {
"content-type": "application/json"
},
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"properties": {
"method": {
"default": "auto",
"description": "Which method to probe first; the other one is always probed too.",
"enum": [
"auto",
"GET",
"POST"
],
"type": "string"
},
"url": {
"description": "Public https address of the x402 resource to check (port 443, a DNS name; no IP addresses, no *.workers.dev).",
"maxLength": 2048,
"minLength": 1,
"type": "string"
}
},
"required": [
"url"
],
"type": "object"
},
"bodyType": {
"enum": [
"json"
],
"type": "string"
},
"headers": {
"additionalProperties": {
"type": "string"
},
"type": "object"
},
"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"
}