eager loading - How to correctly use includes to solve N+1 rails -

i have 3 models:

1)contenttype (parent)

2)recenttools (last 3 childs of contenttype, model tool, recent_tools association using scope of tool)

3)tooltranslation (child of tool)

i want solve n+1, , write includes this. right im stucked:

contenttype.includes(recent_tools: :tool_translation) 

this should work guess accorting guides, includes always returns me full list of tools, instead of recent_tools, , of translations them.

this tool.rb

class tool < applicationrecord   has_one :tool_translation, -> { where(locale: i18n.locale) }, dependent: :destroy    belongs_to :content_type    scope :recent, ->(number){ limit(number) } end 

and content_type model:

class contenttype < applicationrecord   has_many :tools, dependent: :destroy   has_many :recent_tools, -> { recent(3) }, class_name: "tool" end 

where missing? can explain? maybe bad logic recent tools(it needed because need 3 last tools of content_type on main page)? how should write includes correctly? thanks!

hope work

contenttype.includes(:recent_tools, recent_tools: :tool_translation)

in case not, please let me know.