# Api

> Spend preflight for AI agents. Send the x402 PaymentRequired body (v1 or v2) you received, or a cart, plus optional rules (per-payment max, hold threshold, daily cap, allowlists, new-domain days). Returns allow|hold|block with reasons, the cheapest acceptable payment option, and a receipt id. Read-only: never signs, settles, or holds funds. Use before every payment.

- **Domain**: `api.spendpreflight.com`
- **Provider**: api.spendpreflight.com (https://api.spendpreflight.com/)
- **Kind**: paid_api
- **Live-responds (last probe)**: None
- **Signed card**: False
- **Streaming**: False
- **Quality score**: 70%
- **Payment protocol**: x402 · network `eip155:8453` · ≥ $0.01
- **Wallet**: `0xbf4164e07552e4c1b1b1597e72c7acaa3f0a1c58`

## URLs
- Agent card: https://api.spendpreflight.com/
- Page (HTML): https://agenstry.com/agents/api.spendpreflight.com
- Documentation: https://api.spendpreflight.com/v1/preflight