class Grape::Exceptions::Validation

def as_json(*_args)

and headers when converting a validation error to json or string
Remove all the unnecessary stuff from Grape::Exceptions::Base like status 
def as_json(*_args)
  to_s
end

def initialize(params:, message: nil, **args) 

def initialize(params:, message: nil, **args)
  @params = params
  if message
    @message_key = message if message.is_a?(Symbol)
    args[:message] = translate_message(message)
  end
  super(**args)
end