Remove 'attributes' nesting?

Hi,
I have a class extending ActiveYaml::Base as below:

class Item < ActiveYaml::Base
  set_root_path Rails.root.join('db', 'static')
  field :name
end

# items.yml
- id: 1
  name: Animal Welfare
- id: 2
  name: Climate Change
- id: 3
  name: Asylum Seekers

However when I query the data, it always comes back nested under an attributes key.

irb(main):020:0> Item.all.as_json
=> [{"attributes"=>{"id"=>1, "name"=>"Animal Welfare"}}, {"attributes"=>{"id"=>2, "name"=>"Climate Change"}}, {"attributes"=>{"id"=>3, "name"=>"Asylum Seekers"}}]

irb(main):023:0> Item.first.as_json
=> {"attributes"=>{"id"=>1, "name"=>"Animal Welfare"}}

Is there a reason why this has to be the case, or can I remove it somehow? It's a bit annoying because I'll eventually want to start using ActiveRecord, and then we'll have to update the client to stop looking for that key or else start adding it in to the DB records.
Thanks

Reproduce the behavior with the ActiveYaml::Base Item example and the items.yml data shown in the issue, then inspect how Item.all.as_json and Item.first.as_json produce the attributes wrapper. Confirm whether removing that nesting is intended and whether existing ActiveHash serialization behavior depends on it; done means the requested JSON shape is clear and verified without breaking current behavior.