Core

Errors

Standard HTTP status codes plus a typed JSON envelope.

json

{
  "error": {
    "code": "card_declined",
    "type": "invalid_request_error",
    "message": "The card was declined by the issuer.",
    "param": "source.number",
    "decline_code": "insufficient_funds",
    "requestId": "req_3kf91… "
  }
}

Status	Meaning	Description
`200`	OK	Everything worked.
`201`	Created	A new resource was created.
`400`	Bad request	Request is malformed or missing required parameters.
`401`	Unauthorized	Missing or invalid API key.
`402`	Payment failed	Provider declined the charge.
`403`	Forbidden	Key kind is not allowed for this endpoint.
`404`	Not found	Resource does not exist.
`409`	Conflict	Idempotency-Key reused with a different request body.
`422`	Unprocessable entity	No provider in the cascade can accept this charge.
`429`	Too many requests	Rate limit exceeded — back off and retry with jitter.
`500`	Server error	Internal failure. Safe to retry idempotently.