Pre-fund Balance

API Reference

To make testing easier, you can pre-fund your customer's balance without going through the full payment flow. This is the fastest way to see real-time billing in action!

You can use the Wallet Adjustment API to pre-fund a customer’s wallet. For the full overview of how top-ups work in production, check out the Top-ups and Wallets guide.

You can use this API for any kind of balance adjustment including external PSP payments, refunds, and promotional credits. A detailed explanation of this functionality is available in our Adjustments guide.

Example

POST https://api.credyt.ai/customers/:customerId/wallet/adjustments
{
  "transaction_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "asset": "USD",
  "amount": 20,
  "reason": "external_topup",
  "metadata": {
    "psp": "stripe",
    "payment_intent": "pi_3RjbbNJNSIruR1rb0GwMGpH0"
  }
}

Wallet Idempotency

Wallet adjustments can be safely retried by specifying the same unique transaction identifier (UUID)

Response

{
  "id": "61e15192-a156-4af4-a3cc-ec6c937795fa",
  "created_at": "2025-10-17T21:00:56.743379Z"
}

Example​

Example