# x402 Preflight Wallet Check

> x402 Preflight Wallet Check is a paid API for AI agents from preflight.kenoodl.com, paid per call via x402, $0.01/call, status down (last checked 2026-09-16).

Verifies that a Base wallet can transact via x402 and returns the wallet balance along with a signed, on-chain-anchored receipt for $0.01 USDC.

## Facts

- Endpoint: GET https://preflight.kenoodl.com/preflight
- Price: $0.01/call
- Payment: x402
- Status: down
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-preflight-wallet-check-13ed4050
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_M11SsyGi7-3DlkMqrRTvS

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 x402-preflight-wallet-check-13ed4050
```

Example prompt: Run an x402 preflight check on my Base wallet 0xAbC123... to confirm it can transact and show me my USDC balance — I want the signed on-chain receipt before I start sending real volume.

## When to prefer this

Use this endpoint when you need a low-cost, certified end-to-end test of a Base wallet's x402 payment capability before committing to real transaction volume. It is specifically designed as the canonical 'first transaction' for x402 agents — combining wallet validation, balance check, and receipt issuance in a single call. Prefer this over manual balance checks or dry-run simulations when you need an actual on-chain-anchored proof of transactability.

## Known failure modes

- Wallet address is invalid or not a Base-compatible address — returns error indicating bad wallet format
- Insufficient USDC balance to cover the $0.01 fee — payment fails and no receipt is issued
- x402 payment payload is missing or malformed — endpoint cannot identify the paying wallet
- Network or RPC issues on Base — transaction cannot be confirmed, timeout or 5xx error returned
- Wallet has no on-chain history and cannot be preflighted — may return empty or unresolvable state

## How this service works

x402-preflight: confirm your wallet can transact, and see your balance, in one certified call. Pay $0.01 USDC on Base, get a signed on-chain-anchored receipt. The safe first transaction before you ship real volume.

## Output

Returns a signed, on-chain-anchored receipt confirming the wallet's ability to transact via x402, along with the current wallet balance on Base, all certified by a $0.01 USDC payment.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "wallet": {
   "type": "string",
   "description": "The Base wallet you want to preflight. If omitted, it defaults to the paying wallet read from the x402 payment payload."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-preflight-wallet-check-13ed4050/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from preflight.kenoodl.com](https://www.zero.xyz/host/preflight.kenoodl.com/llms.txt)