zen properties are being validated on any map

[KGOH]

For some reason zen tries to valiadate properties on all data coming in, this can be illustrated on a map:
I expect to get error that :zen/tags is not a valid key defined for my map, but I get no errors instead. After I can pass a hash set of symbols it is apparent that it is being validated by the 'zen/tags schema.

  (def ztx (zen.core/new-context {}))

  (zen.core/load-ns ztx '{:ns myns foo {:zen/tags #{zen/schema}
                                        :type zen/map
                                        :keys {:foo {:type zen/string}}}})

  (zen.core/validate ztx #{'myns/foo} {:zen/tags "foo"})
  ;; => {:errors [], :warnings [], :effects []}

  (zen.core/validate ztx #{'myns/foo} {:zen/tags #{'myns/foo}})
  ;; => {:errors
  ;;     [{:message
  ;;       "Expected symbol 'myns/foo tagged with '#{zen/tag}, but only #{zen/schema}",
  ;;       :type "symbol",
  ;;       :path [:zen/tags myns/foo],
  ;;       :schema [myns/foo :property :zen/tags :every myns/foo :tags]}],
  ;;     :warnings [],
  ;;     :effects []}

[KGOH]

Another interesting case:

(zen.core/validate ztx #{'myns/foo} {:zen/tags ["hello"]})
;; => {:errors
;;     [{:message "Expected type of 'symbol, got 'string",
;;       :path [:zen/tags "hello"],
;;       :type "symbol.type",
;;       :schema [myns/foo :property :zen/tags :every "hello" :type]}
;;      {:message "No symbol 'hello found",
;;       :type "string",
;;       :path [:zen/tags "hello"],
;;       :schema [myns/foo :property :zen/tags :every "hello" :tags]}],
;;     :warnings [],
;;     :effects []}