SYNTHORA x402 Endpoint Preflight
VerificationPreflight check for x402 endpoints. Given an endpoint URL or a payTo address, it looks the resource up in the CDP Bazaar catalog, probes it for a live 402 challenge, compares declared against live payTo, and returns a 0-100 scorecard with a pay_ok, caution or do_not_pay verdict, signed with Ed25519.
Pay from $0.01 per request in USDC on Base, settled onchain via the x402 protocol, no signup, no API key needed.
ASSESSMENT
updated 5h agoEvidence-backed signals, not a single score. Click any chip for the proof. Measured values stay read-only; unknown is honest.
reliability 90.5%
- uptime 24h
- 87.5%
- uptime 7d
- 90.5%
- uptime 30d
- 90.5%
- uptime 90d
- 90.5%
- response p95
- 2009ms
- avg response
- 1306ms
- total checks
- 24
compliance A (11/11)
11 of 11 x402 conformance checks pass. Full checklist below.
price $0.01 (p48 in Verification)
- price (min)
- $0.01
- category percentile (min)
- p48 in Verification
- endpoints / prices
- 1 / 1
- model
- flat
- stability
- 100%
risk clean
No deterministic risk flag. Risk fires only on an exact blocklist match, or a reserved-brand name with a mismatched verified payTo. Never from low uptime, a high price, or a model guess.
traction $0.03 30d · 0 buyers
- volume 30d
- $0.03
- buyers 30d
- 0
- settlements 30d
- 2
- last settlement
- 2026-07-21
- top buyer share
- 48% of 30d volume
- trend 7d vs 30d
- 0.11x the 30d daily rate
- networks
- eip155:8453
Attributed pro-quota: this payout address is shared, so volume and buyers are the operator-level figure divided by the services sharing it. A declared convention, not an individually observed measure, and still a conservative undercount.
Top buyer share is a concentration signal, not part of the ranking score.
WHAT IT DOES
ai-derivedVerifies x402 endpoints before payment by checking reachability, catalog presence, and payTo address matching.
- category
- endpoint-verification
- in
- body
- auth
- none
AI-generated summary. The measured data is never altered by it.
ENDPOINTS
| METHOD | PATH | DESCRIPTION | PRICE | NETWORK | ASSET |
|---|---|---|---|---|---|
| POST | /service | 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. | $0.01 | Base | USDC |
REQUEST / RESPONSE EXAMPLE
An unpaid request to POST /service returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.
curl -i -X POST 'https://x402meta.hergertsynthora.com/service'
// 402 response (captured by monitor) · 1 payload · click to expand
[
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x10800a5a5B9d72251566EC651E862A8b4B427dE0",
"amount": "10000",
"scheme": "exact",
"network": "eip155:8453",
"mimeType": "application/json",
"resource": "https://x402meta.hergertsynthora.com/service",
"description": "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.",
"maxAmountRequired": "10000",
"maxTimeoutSeconds": 300
}
],
"freeTier": {
"note": "send header X-WALLET: 0x<your Base address> for a free trial",
"header": "X-WALLET",
"callsPerWallet": 3
},
"resource": {
"url": "https://x402meta.hergertsynthora.com/service",
"mimeType": "application/json",
"description": "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."
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"endpoint_url": "https://api.exa.ai/search"
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"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
}
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"anyOf": [
{
"required": [
"endpoint_url"
]
},
{
"required": [
"payTo"
]
}
],
"properties": {
"prev": {
"type": "object",
"properties": {
"payTo": {
"type": "string"
},
"amount": {
"type": "string"
},
"lastUpdated": {
"type": "string"
}
},
"description": "Optional prior snapshot to detect change (anti-rug)."
},
"payTo": {
"type": "string",
"description": "A payTo address (0x…40hex) to look up in the catalog instead of / in addition to a URL."
},
"endpoint_url": {
"type": "string",
"description": "The x402 endpoint URL to preflight (http/https). Either this or payTo is required."
}
}
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"ok": {
"type": "boolean"
},
"type": "object",
"niche": {
"type": "string"
}
}
}
}
}
}
}
},
"x402Version": 2
}
] UPTIME
RECENT CHECKS
OVER TIME
All charts share the 30d window selected here. Every series is also served as JSON at /api/v1/services/synthora-x402-endpoint-preflight/price, /scores, /volume and /buyers. On-chain volume and distinct buyers are measured over the service's settlement address and are a conservative undercount (only settlements that reach a measured facilitator are counted).
Shared payout address (61 other services). These bars are the full shared address (operator-level), so do not sum them across the services that share it. Where a per-service figure is attributed, the assessment block and the ranking, it is the address total divided pro-quota by the 62 services sharing it: a declared convention, not an individually observed measure.
Shared payout address (61 other services). These bars are the full shared address (operator-level), so do not sum them across the services that share it. Where a per-service buyer count is attributed, the assessment block and the ranking, it is divided pro-quota by the 62 services sharing the address and can be fractional: a declared convention, not an individually observed measure.
COMPLIANCE
11/11 checks pass · grade A- 402 payload captured
- accepts[] array present
- payTo address recoverable
- payTo at accepts[0].payTo (conformant shape)
- payTo is a valid on-chain address
- atomic price declared
- atomic price in a sane range
- asset (token) address declared
- network resolves to CAIP-2
- payment scheme declared
- served over HTTPS
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