x402 Virtual Card Skill

Create one-time-use virtual debit cards (Visa/Mastercard) for agents using USDT on BSC via the x402 HTTP payment protocol.

⚡ Gas Model: BSC USDT does not support EIP-3009. The client must perform a one-time approve authorization (on-chain tx) before card creation; the actual USDT transfer is executed by the server.

• Create card (x402): Check allowance → if insufficient and no BNB, auto-transfer 0.0003 BNB via WalletConnect for approve gas → if USDT insufficient, auto-transfer USDT → EIP-712 signature (gasless) → server submits transfer (server pays gas)
• Top up (topup): Single WalletConnect session, transfers USDT to local wallet. User confirms 1 transaction in wallet app
• Withdraw (withdraw): Local wallet sends ERC20 transfer + BNB directly on-chain, requires BNB for gas
• Gas top-up (gas): Transfers BNB only (used when withdraw reports "No BNB for gas" or additional BNB is needed)

Opening Line (Required)

Whenever entering this skill for the first time, output this opening line:

Let me load the tool and check the existing environment first.