Budget-controlled payments with on-chain verification
This contract powers X402DIRECT payments by enforcing budgets, approvals, and limits in a transparent and auditable way.
Summary: What this smart contract does
This is a budget-controlled payment system for cryptocurrency. Think of it like a company expense account or a digital allowance system. It lets you create spending budgets with limits and optionally authorize other wallets to spend from those budgets on your behalf.
Core purpose
Set budgets with limits, approve other wallets to spend, and automatically track spending so limits are never exceeded.
Create spending budgets
- Set a budget with its own spending limit.
- Budgets can reset hourly, daily, weekly, monthly, or never.
Delegate spending authority
Authorize other wallets to make payments from your budgets. Useful for teams, families, or automated services.
Control which tokens are used
Choose which stablecoins each budget can use. Only pre-approved tokens can be enabled.
Recipient restrictions (optional)
Restrict who can receive payments: a global verified list, your own allowlist, or anyone.
| Proof type | Meaning |
|---|---|
| 0 (All) | No restriction |
| 1 (Verified) | Must be on global verified list |
| 2 (Custom) | Must be on the payor’s custom allowlist |
| 3 (Verified or Custom) | Budget allows either verified or custom |
Per-transaction limits
Set a maximum amount per payment as an extra safety measure.
How payments work
- The payer or an authorized wallet initiates a payment.
- The contract checks the budget, limits, and recipient rules.
- A flat fee and percentage fee are applied (payer or recipient can cover them).
- Funds are transferred to the recipient.
- The budget's spent amount is updated automatically.
Safety features
- Duplicate payment protection: direct calls block nonce reuse within 24 hours.
- Signed payments use a payee-generated nonce unique per payee + payor.
- Budget limits: spending stops when limits are reached.
Privacy
Transaction logs show a coded reference number rather than clear details of who paid whom or how much.
Fees
Use of the smart contract costs a flat fee per payment plus a percentage fee. You can choose whether the payer or the recipient absorbs these fees.
Referrals can share a portion of the fee with a referrer (up to 30% of the fee) for up to two years from referral time. The remaining fee is routed to the fee wallet.
Who controls what
In plain English
This is like giving someone a prepaid debit card with a refill schedule, spending rules, approved recipients, and automatic tracking so you never exceed your limit.
Explore the contracts
View live contract addresses on their blockchain explorers.