Rails I18N (activemodel errors, simple_form labels and hints)

rails_i18n

en:
  # ~~~~~~~~
  # Model Errors
  # ~~~~~~~~
  activemodel:
    errors:
      models:
        bidrequest:
          not_json: "Not a valid JSON"
          url_not_valid: "Not a valid URL"
  #
  # ~~~~~~~~
  # Controller
  # ~~~~~~~~
  bidrequest_failure: "Unable to send the Bid Request"
  bidrequest_error: "Bid Request Error"
  #
  # ~~~~~~~~
  # Simple Form
  # ~~~~~~~~
  simple_form:
    labels:
      bidrequest:
        new:
          title: "Send a Bid Request"
          bid_request: "Bid Request"
          bid_url: "Bidder URL"
    hints:
      bidrequest:
        new:
          bid_request: "Expected format is JSON"
  #
  # ~~~~~~~~
  # View of BidrequestsController#send: app/views/bidrequests/send.html.erb
  #   <%= t(:'.title') %>
  # Cf. http://guides.rubyonrails.org/i18n.html#looking-up-translations 
  #   § 4.1.4 "Lazy" Lookup
  # ~~~~~~~~
  bidrequests:
    send:
      title: "Send a Bid Request"