preferredResources

The resource type values that are considered as candidates when generating rightsizing recommendations. This object resolves any wildcard expressions and returns the effective list of candidate resource type values. It also considers all applicable preferences that you set at the resource, account, and organization level.

To validate that the preference is applied to your last generated set of recommendations, review the effectiveRecommendationPreferences value in the response of the GetAutoScalingGroupRecommendations or GetEC2InstanceRecommendations actions.