# x402-seller-lookup

> x402-seller-lookup is a paid API for AI agents from loop2-quickstart.manhliemcn4euwlu.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-11).

Performs on-demand due-diligence on a single x402 seller wallet, returning live USDC balance, 30-day settlement stats, directory presence, DNS reachability, and a machine-readable allowlist verdict.

## Facts

- Endpoint: GET https://loop2-quickstart.manhliemcn4euwlu.workers.dev/mkt/seller?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-seller-lookup-5cb2d723
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YdtDV_4ll97DW7HEjDjhZ

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-seller-lookup-5cb2d723
```

Example prompt: Before I add 0xAbc123... to my x402 payment allowlist, can you run a due-diligence check on that seller wallet and tell me whether it comes back as ADD_TO_ALLOWLIST, REVIEW, or NO_PRINCIPAL — including their live USDC balance and 30-day settlement stats?

## When to prefer this

Choose this endpoint when you need a single, consolidated due-diligence snapshot on a specific x402 seller wallet before adding them to a buyer allowlist or OAP flow — especially when you need both on-chain settlement attestation and off-chain directory/DNS signals combined into one machine-readable verdict. Prefer it over generic blockchain explorers when you need x402-specific context (PayAI directory, conformance signals) and a ready-to-act verdict rather than raw chain data.

## Known failure modes

- Invalid or malformed wallet address returns an error or empty result
- Wallet address not found on Base chain returns zero balance and NO_PRINCIPAL verdict
- DNS lookup timeout causes reachability field to be null or unresolvable
- Payment of 0.001 USDC not processed results in 402 response before data is returned
- Missing required 'format' query parameter may return a schema validation error

## How this service works

Complete x402 quickstart bundle: v2 Base USDC seller endpoint + EIP-3009 buyer client + deterministic product bundle + tests.

## Output

Returns a JSON object containing the seller's live Base USDC balance, 30-day transaction count (tx_30d), number of unique senders in 30 days (senders_30d), address activity metrics, PayAI directory entries and domains, public DNS reachability status, and a machine-readable verdict string of ADD_TO_ALLOWLIST, REVIEW, or NO_PRINCIPAL.

## 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"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "format"
     ],
     "properties": {
      "format": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "format": {
     "type": "string"
    },
    "example": {
     "type": "string"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "binary",
 "example": "{wallet, usdc_balance, tx_30d, senders_30d, in_directory, verdict}"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-seller-lookup-5cb2d723/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from loop2-quickstart.manhliemcn4euwlu.workers.dev](https://www.zero.xyz/host/loop2-quickstart.manhliemcn4euwlu.workers.dev/llms.txt)