2. Top up with USDC

You fund your account with USDC on Base using x402, an HTTP 402 payment flow. Only confirmed balance is spendable on inference.

Steps

1. From your account, choose an amount (default $10; range $1–$1,000) and start a top-up.
2. The server responds with a 402 challenge describing the exact payment.
3. Sign the EIP-3009 authorization with your wallet.
4. The request is retried with the signed payment and settles on Base.
5. Your balance shows as pending until it confirms (~20 blocks, ~40s), then becomes spendable.

Payer must match

The wallet that pays must be the same wallet that is signed in. Out-of-band transfers are not credited.

Amounts

	Value
Minimum	$1
Recommended	$10
Maximum	$1,000

USDC has 6 decimals; the API expresses amounts in micro-USDC (1 USDC = 1,000,000).

Next

• 3. Set your max price
• Reference: x402 top-up