# x402 Bazaar Rank – Metadata Tag Discovery

> x402 Bazaar Rank – Metadata Tag Discovery is a paid API for AI agents from x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev, paid per call via x402, $0.032/call, status unknown (last checked 2026-10-23).

Returns a ranked list of x402 services tagged 'metadata', scored by real 30-day call volume and payer counts, with a snapshot hash receipt.

## Facts

- Endpoint: GET https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/in-metadata?utm_source=zero.xyz
- Price: $0.032/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-bazaar-rank-metadata-tag-discovery-a2b220cf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gkJURsVuW0gk8kJ8BuGzq

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-bazaar-rank-metadata-tag-discovery-a2b220cf
```

Example prompt: Show me the top 25 x402 services tagged 'metadata', ranked by number of paying wallets over the last 30 days, and include the snapshot hash so I can verify the data freshness.

## When to prefer this

Choose this endpoint when you specifically need ranked, usage-verified discovery of x402 services in the metadata category, backed by real 30-day on-chain payment data rather than self-reported metadata. Prefer it over generic API directories when you want trustworthy popularity signals (payer wallet counts, call volumes) and an auditable snapshot receipt. Not suitable for discovering services outside the x402 protocol or for categories other than metadata.

## Known failure modes

- Payment not included or invalid USDC payment header — returns 402 Payment Required
- No services match the metadata tag filter — returns count:0 with empty services array
- Snapshot data stale or hash mismatch — receipt may reference outdated scoring revision
- Rate limiting or worker timeout on Cloudflare edge — returns 5xx
- Malformed query parameters — returns error or unexpected empty result

## How this service works

An open index of the machine-to-machine (agent) economy. x402 routes: ranked discovery over the live x402 service market, every indexed service scored by real 30-day calls and paying-wallet bounds, with a receipt naming the snapshot hash and scoring revision. /economy routes, for Tempo MPP, Virtuals ACP, Olas, Masumi, ERC-8004 agent registries, Solana agent registries, Base agent contracts and MCP servers (Official MCP Registry): each protocol's published figures (agent or server counts, transactions or payment events; payers and USD volume only where the source publishes them: payers for x402 and Tempo MPP, USD volume for x402 and Virtuals ACP), each with its unit, window and source; units differ, so totals are not summed. L402 and per-service MPP listings are not covered.

## Output

Returns a JSON object with: total matched count, the query parameters used, the route called, a list of up to 25 ranked services each with name, network ID, 30-day call count, price in USD, resource URL, and 30-day payer count, plus a 'declaredBy' field and an ISO timestamp with a snapshot hash for auditability.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "count": 25,
  "query": {
   "by": "payers",
   "op": "top",
   "limit": 25,
   "where": {
    "tag": "metadata"
   }
  },
  "route": "/in-metadata",
  "matched": 359,
  "services": [
   {
    "name": "forecast api",
    "network": "eip155:8453",
    "calls30d": 310,
    "priceUsd": 0.01,
    "resource": "https://api.example.com/forecast",
    "payers30d": 42
   }
  ],
  "declaredBy": "agent",
  "generatedAt": "2026-09-17T12:00:00.000Z"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-bazaar-rank-metadata-tag-discovery-a2b220cf/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev](https://www.zero.xyz/host/x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/llms.txt)