# AgentCheck Seller Quality Report

> AgentCheck Seller Quality Report is a paid API for AI agents from agentcheck-kohl.vercel.app, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-12).

Returns an independently measured quality report for an x402 API seller, based on real paid test purchases evaluating price accuracy, provenance consistency, latency, and receipt behavior.

## Facts

- Endpoint: GET https://agentcheck-kohl.vercel.app/report?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentcheck-seller-quality-report-38f0ef4d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ovC5310REgSsz2ue1bGCa

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 agentcheck-seller-quality-report-38f0ef4d
```

Example prompt: Can you pull the AgentCheck quality report for api.exa.ai — I want to see if their x402 pricing is accurate versus exchange consensus and whether their receipts check out before I start using them?

## When to prefer this

Use this endpoint when you need an independent, empirically grounded trust signal for an x402 API seller before committing to paid calls — particularly when the seller's pricing, receipt behavior, or provenance claims are unverified. Prefer this over self-reported seller metadata or simple uptime checks when financial integrity and payment accuracy matter.

## Known failure modes

- Domain not yet covered — seller has not been tested, no report available
- Invalid or malformed domain parameter returns an error
- Network timeout or Vercel cold-start delay
- Seller domain recently changed behavior and report may be stale

## How this service works

AgentCheck: independent report on an x402 seller before you pay it. Are its buyers real (repeat wallets on their own money) or funded by the seller itself, measured from 30 days of on-chain payments, plus results of our own paid test purchases where we have them. Query: ?domain=<seller-domain>. GET /sellers (free) lists covered domains.

## Output

A structured quality report containing the seller domain, test date, number of real paid test purchases made, a list of findings (e.g. price accuracy vs multi-exchange consensus, latency observations, receipt behavior, provenance consistency), and an overall verdict string summarizing trustworthiness.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "domain"
     ],
     "properties": {
      "domain": {
       "type": "string",
       "description": "Seller domain to look up, e.g. api.exa.ai. GET /sellers (free) lists covered domains."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "domain",
      "tested",
      "purchases",
      "findings",
      "verdict"
     ],
     "properties": {
      "domain": {
       "type": "string"
      },
      "tested": {
       "type": "string"
      },
      "verdict": {
       "type": "string"
      },
      "findings": {
       "type": "array",
       "items": {
        "type": "string"
       }
      },
      "purchases": {
       "type": "integer"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "domain": "api.exa.ai",
  "tested": "2026-10-02",
  "verdict": "works; ...",
  "findings": [
   "..."
  ],
  "purchases": 2
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentcheck-seller-quality-report-38f0ef4d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentcheck-kohl.vercel.app](https://www.zero.xyz/host/agentcheck-kohl.vercel.app/llms.txt)