class Problem
DEFAULT_TYPE = "https://api.example.com/problems/about:blank".freeze
attr_reader :type, :title, :status, :detail, :instance, :extensions
def initialize(status:, title:, detail: nil, type: nil, instance: nil, extensions: {})
class ApplicationError < StandardError
attr_reader :context
class << self
def context_keys(*keys)
@context_keys = keys unless keys.empty?