Credit
The unit an API bills in; each call costs a published number of them.
What it means
Credit-based billing replaces a flat subscription with a prepaid balance. Each call deducts a price that depends on what it does, so cost tracks use.
How Onekey handles it
Every Onekey endpoint has a flat price of 1 to 8 credits shown on its page and returned in metadata.credits_charged. Most are 1 or 5. Credits never expire. GET /v1/account and GET /v1/platforms cost nothing. A call you cannot afford returns 402 INSUFFICIENT_CREDITS and nothing is charged.