Add custom headers to all apis in swagger doc

there is a way to add headers field in one api as document mentions, like below

class API::V1::Teachers < Grape::API
  resource :teachers do
    desc "get all teachers information" do
      headers XAuthToken: {
            description: 'Validates your identity',
            required: true
          },
          XOptionalHeader: {
            description: 'Not really needed',
            required: false
          }
    end
    success: API::V1::Entities::Teachers::Base
    get '' do
      teachers = Teacher.all

      present :teachers, teachers, with: API::V1::Entities::Teachers::Base
    end
  end
end

but is there a way to add same headers to all apis under certain resources or namespace or all of them?

Start with the existing headers option in the desc block and the API::V1::Teachers resource example. Investigate whether headers can be applied at the resource, namespace, or API scope; done means establishing a supported approach and documenting or implementing the selected scope.