Copy page

API essentials

Error semantics

The response envelope

Every response is JSON in a universal envelope:

Code
{
  "status": 200,
  "message": "",
  "response": { "...": "..." }
}

Field	Meaning
status	The real outcome: 200 = success, anything else = error code
message	Human-readable error description (empty on success)
response	Method-specific result; null on failure

A failed call

Code
{
  "status": 400,
  "message": "Invalid signature",
  "response": null
}

Your client must check status in the body of every response:

Code
$body = json_decode($response->getBody(), true);

if (($body['status'] ?? 0) !== 200) {
    throw new ApiException($body['message'] ?? 'Unknown error', $body['status']);
}

return $body['response'];