# Sandbox

Use existing wallets in one self-service routed test USDC flow.

Cleard provider API · 1.4.0 · Base Sepolia test USDC.

[Open the sandbox](https://sandbox.cleard.ai/): Choose provider or direct merchant, enroll funding permissions and create protected checkouts.

Merchant and buyer links open wallet-specific reviews. The merchant accepts bounded authority; the buyer approves its payment. Claims go to the designated reviewer. The application shows payment allocation and separate approved, paid and outstanding amounts.

[Run the complete flow](https://cleard.ai/docs/quickstart.md): Set up access and wallets, then run a payment, claim and refund under either funding mode.