# Base Merchant Trust Assessment

> Base Merchant Trust Assessment is a paid API for AI agents from base-agent-preflight.bytoken2023.workers.dev, paid per call via x402, $0.1/call, status unknown (last checked 2026-09-13).

Evaluates the trustworthiness and risk profile of a Base blockchain merchant address before making payments

## Facts

- Endpoint: GET https://base-agent-preflight.bytoken2023.workers.dev/v1/x402/base/merchant-trust
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-merchant-trust-assessment-bcb32674
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9_aYo0yYxleHkQV0EtV4J

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 base-merchant-trust-assessment-bcb32674
```

Example prompt: Before I pay this merchant, can you check how trustworthy the Base address 0x1234567890abcdef1234567890abcdef12345678 is — what's its risk score and are there any flags I should know about?

## When to prefer this

Use this endpoint when an AI agent is about to make or authorize a payment to a Base blockchain merchant address and needs a risk preflight check. Ideal for x402-based commerce flows where the agent must validate merchant safety before executing a USDC transfer. Choose this over generic blockchain explorers when you need a structured, machine-readable risk score and flags rather than raw transaction history.

## Known failure modes

- Invalid or malformed address (not matching ^0x[a-fA-F0-9]{40}$) returns validation error
- Unknown or brand-new address with no on-chain history may return empty activity data
- Payment failure for the $0.03 USDC x402 toll results in 402 response
- Rate limiting or worker timeout returns 5xx error
- Address exists but has no trust signals, resulting in a neutral/inconclusive assessment

## How this service works

Machine-payable service intelligence for discovering, verifying, and monitoring identity, risk, authorization, execution-preflight, and evidence APIs before autonomous agents spend.

## Output

Returns a JSON object with network identifier (eip155:8453), product name, and an assessment object containing: a risk_score (numeric), risk_level (e.g. 'low'), and a flags array listing any red flags. May also include activity, identity, and provenance objects with additional merchant context.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "pattern": "^0x[a-fA-F0-9]{40}$",
       "description": "Base merchant payment recipient address."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "network": {
       "type": "string"
      },
      "product": {
       "type": "string"
      },
      "activity": {
       "type": "object"
      },
      "identity": {
       "type": "object"
      },
      "assessment": {
       "type": "object"
      },
      "provenance": {
       "type": "object"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "network": "eip155:8453",
  "product": "x402-merchant-trust",
  "assessment": {
   "flags": [],
   "risk_level": "low",
   "risk_score": 0
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-merchant-trust-assessment-bcb32674/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from base-agent-preflight.bytoken2023.workers.dev](https://www.zero.xyz/host/base-agent-preflight.bytoken2023.workers.dev/llms.txt)