curl --request GET \
  --url https://api.httpayer.com/balance \
  --header 'x-api-key: <api-key>'

{
  "account_id": "<string>",
  "mainnet": {
    "credits_balance": 50000,
    "daily_limit": 100000,
    "daily_spend": 15500,
    "daily_remaining": 84500
  },
  "testnet": {
    "daily_limit_usd": 500,
    "today_spent_usd": 12.5,
    "remaining_usd": 487.5
  }
}