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x402meta Preflight & Reputation Service
x402
x402meta Preflight & Reputation Service is a paid API for AI agents from x402meta.hergertsynthora.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).
Verifies an x402 payment endpoint before paying by checking reachability, catalog listing, and payTo address integrity — returning a 0-100 scorecard with a pay/caution/do-not-pay verdict.
Price / call$0.01
Success—
StatusUnknown
How this service works
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.
Output
Returns a 0-100 integrity scorecard, a letter grade, structured reason codes, reachability status, whether the endpoint appears in the CDP Bazaar catalog (with serviceName, declared payTo, price, network, tags, last_seen), whether the live 402-challenge payTo matches the catalog's payTo (payTo_match), and — if a prior snapshot was supplied — a change-detection flag indicating if the endpoint was repriced or redirected since the last observation. The final field is an actionable verdict: pay_ok, caution, or do_not_pay.
Example use cases
Example prompt
“Before we pay this x402 endpoint at https://api.someservice.com/data, run a preflight check to verify the payTo address matches the CDP Bazaar catalog and tell me if it's safe to pay — also compare against our last snapshot where payTo was 0xABC123 and amount was 0.01 USDC from last Tuesday.”
Technical details
Endpoint
POSThttps://x402meta.hergertsynthora.com/serviceWhen to prefer
Use this endpoint whenever an AI agent, wallet, or router needs to verify an x402 payment target before committing funds — especially when paying third-party or unknown x402 endpoints where hijacking, repricing, or dead endpoints are a risk. Prefer this over trusting catalog data alone because it cross-checks the live 402 challenge against catalog records. Use before every payment if zero-trust is required, or whenever a prior snapshot suggests a change may have occurred.
Side effects
- Endpoint URL unreachable — probe returns reachability=false, verdict=do_not_pay
- Endpoint not found in CDP Bazaar catalog — listing absence flagged in reason codes
- payTo mismatch between live 402 challenge and catalog — payTo_match=false, verdict=do_not_pay or caution
- Change detected vs prior snapshot — amount or payTo differs, anti-rug flag set
- Malformed endpoint_url or payTo input — validation error returned
- Ambiguous or stale catalog entry — low freshness score, caution verdict
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| prev | object | Optional prior snapshot to detect change (anti-rug). |
| payTo | string | A payTo address (0x…40hex) to look up in the catalog instead of / in addition to a URL. |
| endpoint_url | string | The x402 endpoint URL to preflight (http/https). Either this or payTo is required. |
Output
Schema · Response
{
"type": "json",
"example": {
"ok": true,
"niche": "x402meta",
"result": {
"host": "api.exa.ai",
"payTo": "0x6d6e695b09861467c7d462f5aaf31cf3540b9192",
"signed": true,
"catalog": {
"payTo": "0x6d6E695b09861467c7d462f5AAF31cF3540B9192",
"amount": "7000",
"network": "eip155:8453",
"resource": "https://api.exa.ai/search",
"last_seen": "2026-07-07T21:49:52.202Z",
"matched_by": "endpoint",
"serviceName": "exa-search"
},
"changed": null,
"verdict": "pay_ok",
"reachable": true,
"scorecard": {
"grade": "B",
"score": 88,
"changed": null,
"reachable": true,
"in_catalog": true,
"payTo_match": true,
"reason_codes": [
"reachable",
"in_catalog",
"emits_402",
"payto_match",
"challenge_wellformed",
"listing_fresh"
],
"listing_age_days": 1,
"requires_payment": true,
"challenge_wellformed": true
},
"in_catalog": true,
"payTo_live": "0x6d6e695b09861467c7d462f5aaf31cf3540b9192",
"payTo_match": true,
"endpoint_url": "https://api.exa.ai/search",
"final_status": 402,
"live_challenge": {
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"payTo": "0x6d6E695b09861467c7d462f5AAF31cF3540B9192",
"amount": "7000",
"network": "eip155:8453"
},
"payTo_declared": "0x6d6e695b09861467c7d462f5aaf31cf3540b9192",
"service_version": "1.0",
"requires_payment": true
}
}
}Tags
x402
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