# Merchant x402 Listing Honesty Gate

> Merchant x402 Listing Honesty Gate is a paid API for AI agents from k2so-8080.on.ascii.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Grades whether a discovery-listed x402 merchant's advertised terms (price, description, tags) match the live 402 challenge reality before an agent pays

## Facts

- Endpoint: GET https://k2so-8080.on.ascii.dev/api/services/merchant-x402-listing-honesty-gate
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/merchant-x402-listing-honesty-gate-6fa267c2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8sSeOVtPIdQYGrVAXMHLu

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 merchant-x402-listing-honesty-gate-6fa267c2
```

Example prompt: Before my agent pays that x402 merchant I found on the marketplace, run the honesty gate to check if their advertised price and service description actually match what the live 402 challenge is asking for.

## When to prefer this

Use this endpoint when an AI agent has discovered an x402 merchant through a marketplace or directory (agentic.market, bazaar, etc.) and needs to verify listing accuracy before committing a payment. Prefer it over generic x402 payment safety checks when the specific concern is listing honesty — i.e., whether the advertised price and terms match the live 402 challenge — rather than scam detection or wallet risk preflight.

## Known failure modes

- Listed URL does not return a 402 challenge (service may be down or not x402-enabled)
- Advertised price units are ambiguous or in different denominations making comparison unreliable
- Network or scheme mismatch cannot be resolved to a clear verdict
- Probe of live URL times out before challenge can be captured
- Missing required listing fields make comparison incomplete

## How this service works

Deterministic procedure for grading whether a discovery-listed x402 merchant's advertised terms match live reality before an agent pays. Inputs: the listing (advertised price, service description, tags), the live 402 challenge probe result (actual price in atomic units, network, scheme, payTo), and the paid or unpaid response shape. Procedure: (1) probe the listed URL without paying and record the challenge or its absence, (2) compare advertised price against the challenge price in atomic units

## Output

Returns a structured verdict with an 'ok' boolean, a 'brief' prose explanation of the decision procedure, the generation source (llm/reasoning/deterministic), an ISO-8601 timestamp, and the service slug — indicating whether the merchant's advertised listing terms match the live 402 challenge reality

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "meta": {
       "enum": [
        "0",
        "1"
       ],
       "type": "string",
       "description": "Set to 1 for free metadata JSON (no payment required)"
      },
      "topic": {
       "type": "string",
       "description": "Optional topic override for the decision procedure"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "title": "Merchant x402 Listing Honesty Gate paid response",
     "$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": {
         "type": "string"
        },
        
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/merchant-x402-listing-honesty-gate-6fa267c2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from k2so-8080.on.ascii.dev](https://www.zero.xyz/host/k2so-8080.on.ascii.dev/llms.txt)