x402 preflight / reputation — verify BEFORE you pay
x402 preflight / reputation — verify BEFORE you pay. Give it an x402 endpoint_url (or a payTo address) and it returns, in one cheap deterministic call: is the resource reachable, is it present in the CDP Bazaar discovery catalog (serviceName, declared payTo, price, network, tags, last_seen), and — the key integrity check — does the payTo the endpoint actually demands in its live HTTP 402 challenge MATCH the payTo the catalog advertises (payTo_match). It runs a keyless HEAD/OPTIONS/402 probe that never moves funds, extracts the real payTo/amount/asset/network from the challenge, scores listing freshness, and — if you pass a prev snapshot {payTo,amount,lastUpdated} — flags whether the endpoint changed since you last saw it (anti-rug). Output is a 0-100 scorecard + letter grade + reason codes + an actionable verdict (pay_ok / caution / do_not_pay). For any router, wallet agent or M2M client that pays third-party x402 endpoints and needs to avoid paying a hijacked, dead, or repriced resource. Deterministic, no LLM, Ed25519-signed. 0.01 USDC via x402 on Base. SYNTHORA.
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://x402meta.hergertsynthora.com/service
| Category | Market data |
|---|---|
| Provider host | x402meta.hergertsynthora.com |
| 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 |
|---|---|---|---|---|
| 2026-09-24 | valid payment request | 402 | $0.01 | 1265 ms |
Example input (from the provider)
{
"body": {
"endpoint_url": "https://api.exa.ai/search"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"anyOf": [
{
"required": [
"endpoint_url"
]
},
{
"required": [
"payTo"
]
}
],
"properties": {
"endpoint_url": {
"description": "The x402 endpoint URL to preflight (http/https). Either this or payTo is required.",
"type": "string"
},
"payTo": {
"description": "A payTo address (0x\u202640hex) to look up in the catalog instead of / in addition to a URL.",
"type": "string"
},
"prev": {
"description": "Optional prior snapshot to detect change (anti-rug).",
"properties": {
"amount": {
"type": "string"
},
"lastUpdated": {
"type": "string"
},
"payTo": {
"type": "string"
}
},
"type": "object"
}
},
"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": {
"niche": {
"type": "string"
},
"ok": {
"type": "boolean"
},
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}