# Quack AI Q402 Agent Trust Monitor

> Quack AI Q402 Agent Trust Monitor is a paid API for AI agents from q402.quackai.ai, paid per call via x402, $0.15/call, status unknown (last checked 2026-09-15).

Fetches on-chain reputation, identity registration, and recent activity data for an EVM wallet address to assess its trustworthiness before sponsoring gasless transactions.

## Facts

- Endpoint: GET https://q402.quackai.ai/api/x402/agent-trust/%7Baddress%7D/monitor
- Price: $0.15/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quack-ai-q402-agent-trust-monitor-e5c5455d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XfCSqejQ8cMbcqD2rldgv

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 quack-ai-q402-agent-trust-monitor-e5c5455d
```

Example prompt: Can you check the trust and on-chain reputation for wallet address 0x70997970C51812dc3A010C7d01b50e0d17dc79C8 — I want to know if it's ERC-8004 registered and how active it's been on Base recently before I sponsor its gas?

## When to prefer this

Choose this endpoint when you need to assess the trustworthiness of an EVM wallet address before sponsoring gasless transactions or granting access to on-chain services. It combines ERC-8004 identity registry checks across BSC and Base with recent on-chain activity analysis in a single call, making it ideal for anti-fraud, airdrop eligibility, or agent authorization workflows on EVM chains. Prefer it over generic blockchain explorers when you need structured reputation data with a gas sponsorship context.

## Known failure modes

- Invalid or malformed EVM address returns an error or empty result
- Address not found on-chain returns null reputation and empty ERC-8004 registrations
- RPC timeout or Base mainnet unavailability may cause incomplete on-chain activity data
- Payment failure (insufficient USDC balance) prevents the call from completing
- Rate limiting may occur under high call volume

## How this service works

Q402 is a gasless payment protocol for EVM chains. Your users pay zero gas. You sponsor it, invisibly and instantly.

## Output

Returns a JSON object containing: ERC-8004 identity registration status (checked on BSC and Base), on-chain transaction count bucket for the address (e.g. '10-49'), whether recent activity was detected in the last 900 blocks (~30 min) on Base mainnet, a reputation field (may be null), a payment receipt ID, the price paid in USDC, and the timestamp of the lookup.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "paidAt": "2026-08-19T05:00:00.000Z",
  "address": "0x70997970C51812dc3A010C7d01b50e0d17dc79C8",
  "erc8004": {
   "source": "ERC-8004 IdentityRegistry — BSC (0x8004A169FB4a3325136EB29fA0ceB6D2e539a432) and Base queried",
   "isRegistered": false,
   "registrations": []
  },
  "receipt": "atx_c5d6e7f8a9b0c1d2e3f4a3b4",
  "priceUsdc": 0.15,
  "reputation": null,
  "onChainActivity": {
   "source": "Base mainnet eth_getTransactionCount (public RPC; scan window 900 blocks ≈ 30 min)",
   "txCountBucket": "10-49",
   "recentActivityDetected": false,
   "recentActivityWindowBlocks": 900
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/quack-ai-q402-agent-trust-monitor-e5c5455d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from q402.quackai.ai](https://www.zero.xyz/host/q402.quackai.ai/llms.txt)