# x402check Credit Top-Up

> x402check Credit Top-Up is a paid API for AI agents from x402check.xyz, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-12).

Adds a USD credit balance to an x402check account, enabling pre-payment risk checks for agents and wallets

## Facts

- Endpoint: POST https://x402check.xyz/v1/credits?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402check-credit-top-up-69ba776c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Zqumlhc3UrpImhjiNxzYq

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 x402check-credit-top-up-69ba776c -d '<json body>'
```

Example prompt: Add $10 in credits to my x402check account so I can run OFAC and phishing risk checks on transactions.

## When to prefer this

Use this endpoint when you need to pre-fund an x402check account before running risk checks such as OFAC SDN screening, phishing/drainer feed lookups, transaction simulation, or injected-instruction analysis. This is a balance top-up step, not the risk check itself — call this first when your credit balance is low or depleted.

## Known failure modes

- Invalid or missing amount_usd returns a 400 error
- Payment failure (insufficient USDC or wallet error) results in no credit being applied
- Network timeout during payment processing may leave credit state ambiguous
- amount_usd of zero or negative values rejected
- Account not found or authentication failure returns 401/403

## How this service works

Pre-payment risk checks for x402 agents and wallets: OFAC SDN, phishing and drainer feeds, a live watch of drainer infrastructure, transaction simulation and injected-instruction analysis. Every verdict is an ES256 attestation that states which checks ran.

## Output

Returns the updated USD balance, the amount credited, and optionally a session token confirming the credit transaction on the x402check account.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "amount_usd"
 ],
 "properties": {
  "amount_usd": {
   "type": "number"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "balance_usd"
 ],
 "properties": {
  "token": {
   "type": "string"
  },
  "balance_usd": {
   "type": "string"
  },
  "credited_usd": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402check-credit-top-up-69ba776c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402check.xyz](https://www.zero.xyz/host/x402check.xyz/llms.txt)