{
    "error": "This token doesn't have permission to access this endpoint"
}
When we detect an error in the request, we will return a HTTP 400 or 401 response, and a JSON payload with a single key (error) containing the error message. If you aren’t receiving errors, make sure you’ve set “Accept: application/json” in your request headers. 
{
    "error": "This token doesn't have permission to access this endpoint"
}