# minia2a x402 Payment Audit (Black-Box Buyer Trust Check)

> minia2a x402 Payment Audit (Black-Box Buyer Trust Check) is a paid API for AI agents from minia2a.uk, paid per call via x402, $5/call, status unknown (last checked 2026-09-15).

Performs a black-box security audit of an x402 payment endpoint to verify it properly rejects forged transaction hashes, invalid signatures, and replay attacks before you pay — returning SAFE, RISK, or NOT_X402.

## Facts

- Endpoint: GET https://minia2a.uk/x402/x402-payment-audit
- Price: $5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/minia2a-x402-payment-audit-black-box-buyer-trust-check-fd86ee72
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_vq6rW1gsPqwmNFtHQ4iYD

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 minia2a-x402-payment-audit-black-box-buyer-trust-check-fd86ee72
```

Example prompt: Before I pay this x402 API, run a black-box audit on it to check whether it actually validates payments — I need to know if it would reject a forged txHash or a replayed signature, and get back a SAFE, RISK, or NOT_X402 verdict.

## When to prefer this

Use this endpoint when you are a buyer or agent about to pay an x402-gated API and want to confirm the endpoint actually enforces payment integrity before committing USDC. Prefer this over manual inspection when you cannot read the server-side source code (black-box scenario). Also prefer this over the white-box source audit endpoint when you only have the live URL and no access to the implementation code.

## Known failure modes

- Endpoint unreachable or returns non-HTTP response — audit cannot complete
- Target endpoint uses non-standard x402 implementation that confuses probing — may return NOT_X402 incorrectly
- Network timeout probing the target — incomplete verdict
- Target endpoint rate-limits audit probe requests — partial results
- Ambiguous payment verification behavior — may return RISK with low confidence

## How this service works

Black-box check: does the x402 endpoint verify payment (reject forged txHash/signature/replay) before delivering? Buyer-side trust check before you pay. Returns SAFE/RISK/NOT_X402.

## Output

Returns one of three verdict strings: SAFE (the endpoint correctly rejects forged txHash, invalid signatures, and replay attacks — safe to pay), RISK (the endpoint has detectable weaknesses in payment verification — payment fraud possible), or NOT_X402 (the endpoint does not appear to implement the x402 payment protocol at all). May include additional detail on which specific checks passed or failed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string"
    },
    "method": {
     "type": "string"
    },
    "bodyType": {
     "type": "string"
    },
    "queryParams": {
     "type": "object"
    }
   }
  },
  "output": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/minia2a-x402-payment-audit-black-box-buyer-trust-check-fd86ee72/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from minia2a.uk](https://www.zero.xyz/host/minia2a.uk/llms.txt)