Errors

Errors use standard HTTP status codes and a JSON body:

{
  "error": {
    "code": "invalid_request",
    "message": "must be at least 0.50",
    "param": "amount"
  }
}

Field	Description
`code`	Stable, machine-readable code (below). Branch on this.
`message`	Human-readable explanation. May change; don’t parse it.
`param`	The request parameter at fault, when there is one

Codes

Status	Code	Meaning	What to do
`400`	`invalid_request`	A parameter is missing or invalid	Fix the request; see `param`
`401`	`unauthorized`	Missing, invalid or revoked credential	Check the key and its mode
`403`	`forbidden`	The account is suspended	Contact support
`404`	`not_found`	The resource does not exist in this mode	Check the id and that you use the right mode’s key
`409`	`conflict`	The request conflicts with the current state (for example the payment is no longer awaiting payment)	Fetch the payment and act on its status
`422`	`method_unavailable`	The token and network can’t be used for this payment	Offer another method
`429`	`rate_limited`	Too many requests of this kind	Slow down; for addresses, create a new payment
`500`	`internal_error`	Something went wrong on our side	Retry with backoff; contact support with the `Request-Id`
`503`	`network_busy`	A blockchain network provider is busy	Retry after the `Retry-After` header (seconds)

Retry 500 and 503 with exponential backoff. Creating a payment is safe to retry with the same payment_id: you never get a duplicate.