# Agent Buyer Identity Preflight | x402 Purchase Governance

> Agent Buyer Identity Preflight | x402 Purchase Governance is a paid API for AI agents from base-agent-preflight.bytoken2023.workers.dev, paid per call via x402, $0.075/call, status unknown (last checked 2026-09-14).

Performs pre-purchase due diligence on an AI agent's wallet and buyer identity before it executes an x402 API payment, assessing risk, role fit, and approval policy compliance.

## Facts

- Endpoint: GET https://base-agent-preflight.bytoken2023.workers.dev/v1/x402/base/payment-due-diligence-bundle
- Price: $0.075/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-buyer-identity-preflight-x402-purchase-governance-20661ae3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ebPJDPFUoA0mXxSIEaBWo

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 agent-buyer-identity-preflight-x402-purchase-governance-20661ae3
```

Example prompt: Before my agent at wallet 0xABCDEF1234567890ABCDEF1234567890ABCDEF12 pays merchant 0x9876543210ABCDEF9876543210ABCDEF98765432 for that x402 API, run a payment due diligence check to make sure the buyer identity fits, the risk is low, and there are no flags blocking the purchase.

## When to prefer this

Use this endpoint when an AI agent needs to perform a governance and risk check before executing an x402 micropayment on the Base network — particularly when the product is sensitive, high-value, or subject to approval policies. Prefer this over generic wallet-balance checks when you need buyer role validation, risk scoring, and policy compliance in a single preflight call specific to the x402 purchase flow.

## Known failure modes

- Missing required wallet_address or merchant_address returns a 400 validation error
- Invalid Ethereum address format causes schema rejection
- Unrecognized or unsupported wallet returns empty identity object with unknown risk
- Transaction hash not found on Base returns null provenance
- Timeout or upstream blockchain node unavailability causes 503
- High risk score returned but no actionable flag details provided

## 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 containing the Base network identifier, product name, a risk assessment with risk_score (numeric), risk_level (e.g. 'low'), and a flags array listing any compliance or policy violations. May also include identity, activity, and provenance sub-objects providing wallet analysis detail.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "merchant_address",
      "wallet_address"
     ],
     "properties": {
      "tx": {
       "type": "string",
       "pattern": "^0x[a-fA-F0-9]{64}$",
       "description": "Optional transaction hash for payment proof and receipt evidence."
      },
      "since": {
       "type": "string",
       "pattern": "^\\d{4}-\\d{2}-\\d{2}T.+Z$",
       "description": "Return wallet activity observed at or after this timestamp."
      },
      "from_block": {
       "type": "string",
       "pattern": "^[0-9]+$",
       "description": "Return event logs from this Base block onward."
      },
      "wallet_address": {
       "type": "string",
       "pattern": "^0x[a-fA-F0-9]{40}$",
       "description": "Base buyer or agent wallet to analyze."
      },
      "expected_amount": {
       "type": "string",
       "pattern": "^[0-9]+(?:\\.[0-9]{1,6})?$",
       "description": "Expected USDC amount for payment-proof verification."
      },
      "contract_address": {
       "type": "string",
       "pattern": "^0x[a-fA-F0-9]{40}$",
       "description": "Contract or address whose event logs should be monitored."
      },
      "merchant_address": {
       "type": "string",
       "pattern": "^0x[a-fA-F0-9]{40}$",
       "description": "Base merchant or API payment recipient address."
      },
      "expected_recipient": {
       "type": "string",
       "pattern": "^0x[a-fA-F0-9]{40}$",
       "description": "Expected USDC recipient for payment-proof verification."
      }
     }
    }
   },
   "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"
      }
     
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "network": "eip155:8453",
  "product": "base-payment-due-diligence-bundle",
  "assessment": {
   "flags": [],
   "risk_level": "low",
   "risk_score": 0
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-buyer-identity-preflight-x402-purchase-governance-20661ae3/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)