# x402meta Preflight & Reputation Service

> 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.

## Facts

- Endpoint: POST https://x402meta.hergertsynthora.com/service
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402meta-preflight-reputation-service-f660fab2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FYDsVqsJMgZxqnYfz9vq8

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability x402meta-preflight-reputation-service-f660fab2 -d '<json body>'
```

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.

## When to prefer this

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.

## Known failure modes

- 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

## 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.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "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."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "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
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402meta-preflight-reputation-service-f660fab2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402meta.hergertsynthora.com](https://www.zero.xyz/host/x402meta.hergertsynthora.com/llms.txt)