# Mekler AI – API Listing Visibility Checker

> Mekler AI – API Listing Visibility Checker is a paid API for AI agents from api.mekler.ai, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-17).

Monitors whether a paid API endpoint is currently listed and discoverable across x402scan, CDP Bazaar, and Agentic Market, returning dated evidence and change alerts.

## Facts

- Endpoint: POST https://api.mekler.ai/v1/services/listings/check-listing-visibility?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mekler-ai-api-listing-visibility-checker-1e1a9f96
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_X0yvUv27A6wc4xfKMmHZM

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 mekler-ai-api-listing-visibility-checker-1e1a9f96 -d '<json body>'
```

Example prompt: Check if my paid API at https://api.mekler.ai/v1/email/domains/check-mail-configuration is currently listed and discoverable across x402scan, Bazaar, and Agentic Market — search for it using the queries 'email domain check' and 'MX record validator' and tell me if there are any changes from last time.

## When to prefer this

Choose this endpoint when you need to verify or continuously monitor whether a specific paid API endpoint is discoverable across x402-ecosystem marketplaces (x402scan, CDP Bazaar, Agentic Market). It is the right choice for API publishers who want evidence-backed confirmation of listing presence, description drift detection, or buyer query visibility — particularly for x402 protocol-based services. Prefer it over manual marketplace checks when you need dated, structured evidence and polling continuity via cursor.

## Known failure modes

- Resource URL not found in any checked directory — returns status with zero positive matches
- Timeout on one or more directories — affected marketplace results marked as unknown/partial
- Invalid merchant wallet address format — schema validation error before request is processed
- Poll ID not recognized or expired — cursor-based continuation fails and full re-check is needed
- Malformed resource URI — request rejected at input validation
- Rate or request limit reached — request_limit field indicates remaining capacity

## How this service works

Monitor one paid API operation across x402scan, CDP Bazaar and Agentic Market. Check exact listing presence, one to three buyer queries and optional description drift. Return dated evidence, confirmed change alerts, private history and the next polling request. Partial coverage and timeouts stay unknown; no ranking or indexing guarantee.

## Output

Returns a JSON object with the listing check status ('ok' or error), the resource URL checked, the UTC timestamp of the check, directory attempt counts, a request limit indicator, and supplier/infrastructure cost data. Includes dated evidence of listing presence or absence across checked marketplaces, change alerts if drift is detected, and a cursor for the next polling request. Partial coverage and timeouts are flagged as unknown.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "cursor": {
   "type": "string",
   "maxLength": 16000,
   "minLength": 1
  },
  "method": {
   "enum": [
    "GET",
    "POST"
   ],
   "type": "string",
   "default": "POST"
  },
  "poll_id": {
   "type": "string",
   "pattern": "^[a-zA-Z0-9_-]{16,64}$"
  },
  "queries": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 160,
    "minLength": 2
   },
   "maxItems": 3,
   "minItems": 1,
   "uniqueItems": true
  },
  "expected": {
   "type": "object",
   "properties": {},
   "additionalProperties": false
  },
  "merchant": {
   "type": "string",
   "pattern": "^(0x[a-fA-F0-9]{40}|[1-9A-HJ-NP-Za-km-z]{32,44})$"
  },
  "resource": {
   "type": "string",
   "format": "uri",
   "maxLength": 1024
  },
  "market_slug": {
   "type": "string",
   "pattern": "^[a-z0-9][a-z0-9-]{0,127}$"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "cost": {
   "request_limit": 24,
   "directory_attempts": 6,
   "supplier_charge_usd": "0",
   "infrastructure_actual_usd": null
  },
  "status": "ok",
  "resource": "https://api.mekler.ai/v1/email/domains/check-mail-configuration",
  "checked_at": 1792155600
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mekler-ai-api-listing-visibility-checker-1e1a9f96/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.mekler.ai](https://www.zero.xyz/host/api.mekler.ai/llms.txt)