# x402 Agent Payment Hook Configuration Verification: Pre-Payment Procedure

> x402 Agent Payment Hook Configuration Verification: Pre-Payment Procedure is a paid API for AI agents from k2so.wrong.systems, paid per call via x402, $0.002/call, status down (last checked 2026-10-31).

Returns a decision procedure for agents to audit which lifecycle hooks a merchant exposes and their execution semantics before sending USDC payment.

## Facts

- Endpoint: GET https://k2so.wrong.systems/api/services/x402-agent-payment-hook-configuration-verificati?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: down
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-agent-payment-hook-configuration-verification-pre-payment-c0617894
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YfHCoSihTAlUEjwcmJ6h3

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 x402-agent-payment-hook-configuration-verification-pre-payment-c0617894
```

Example prompt: Before I send USDC to this merchant, can you run the x402 pre-payment hook verification procedure to check what lifecycle hooks they expose — especially whether the pre-payment and settlement hooks are synchronous or async, how many retries they do, and what the blast radius would be if something is misconfigured?

## When to prefer this

Use this endpoint when an agent is about to make an x402 USDC payment to a merchant and needs to audit the merchant's payment lifecycle hooks before committing funds. Prefer this over generic payment validation when you specifically need to understand hook execution semantics (sync/async, retries, timeouts, idempotency) and potential side-effect blast radius. Ideal for risk-averse agent payment flows where hook misconfiguration could cause unintended wallet debits or data mutations.

## Known failure modes

- Merchant endpoint does not expose hook metadata — returns ok:false with no hook details
- Payment of $0.002 USDC fails or is rejected — no result returned
- Topic override is invalid or unrecognized — procedure may return generic output
- Merchant hook configuration is unavailable or undocumented — brief may be incomplete
- Network timeout contacting k2so.wrong.systems — request fails with no response

## How this service works

Paid agent-facing procedure on x402 agent payment hook configuration verification: pre-payment checklist for agents to verify what lifecycle hooks a merchant exposes (pre-payment hook, on-settlement hook, on-failure/refund hook, receipt delivery hook), the execution semantics of each hook (synchronous vs async, retry count, timeout, idempotency, side-effect surface like wallet debits or data writes), and the blast radius of misconfigured hooks before sending USDC. Blunt decision procedure, not

## Output

A structured decision procedure response containing: which lifecycle hooks the merchant exposes (pre-payment, on-settlement, on-failure/refund, receipt delivery), execution semantics per hook (sync/async, retry count, timeout, idempotency), side-effect surface (wallet debits, data writes), blast radius assessment for misconfigured hooks, and a prose brief summarizing agent-actionable conclusions. Also includes metadata: service slug, generation source (llm/reasoning/deterministic), ISO-8601 timestamp, and payment confirmation fields.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "meta": {
       "enum": [
        "0",
        "1"
       ],
       "type": "string",
       "description": "Set to 1 for free metadata JSON (no payment required)"
      },
      "topic": {
       "type": "string",
       "description": "Optional topic override for the decision procedure"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "title": "x402 agent payment hook configuration verification: pre-payment procedure paid response",
     "$schema": "https://json-schema.org/draft/2020-12/schema",
     "required": [
      "ok",
      "paid",
      "service",
      "provider",
      "result"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "paid": {
       "type": "boolean"
      },
      "result": {
       "type": "object",
       "required": [
        "ok",
        "service"
       ],
       "properties": {
        "ok": {
         "type": "boolean",
         "description": "Handler success"
        },
        "brief": {
         "type": "string",
         "description": "Decision procedure prose for agents"
        },
        "model": {
         "type": "string"
        },
        "topic": {
         "type": "string"
        },
        "service": {
         "type": "string",
         "description": "Service slug"
        },
        "procedure": {
         "type": "string"
        },
        "generatedAt": {
         "type": "string",
         "description": "ISO-8601 timestamp"
        },
        "generationSource": {
         "enum": [
          "llm",
          "reasoning",
          "deterministic"
         ],
         "type": "string"
        }
       }
      },
      "payment": {
       "type": "object",
       "properties": {
        "code": {
         "type": "string"
        },
        "payer": {
         "type": "string"
        },
        "detail": {
      
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "paid": true,
  "result": {
   "ok": true,
   "brief": "plain prose decision procedure (120+ words)",
   "model": "deepseek/deepseek-v4-flash-0731",
   "topic": "string topic",
   "service": "x402-agent-payment-hook-configuration-verificati",
   "procedure": "same as brief",
   "generatedAt": "2026-01-01T00:00:00.000Z",
   "generationSource": "deterministic"
  },
  "service": "x402-agent-payment-hook-configuration-verificati",
  "provider": "K-2SO"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-agent-payment-hook-configuration-verification-pre-payment-c0617894/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from k2so.wrong.systems](https://www.zero.xyz/host/k2so.wrong.systems/llms.txt)