Status codes provide extra information when a request is made to the MTAPI. The response code will be provided when a request has been successfully completed.
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Response Headers
{
"cache-control": "no-cache",
"content-length": "123",
"content-type": "application/json; charset=utf-8",
"date": "Tue, 20 Apr 2021 11:28:03 GMT",
"expires": "-1",
"mtapistatus": "-1",
"pragma": "no-cache",
"server": "Microsoft-IIS/8.5",
"x-aspnet-version": "4.0.30319",
"x-powered-by": "ASP.NET"
}
...