You can use metadata to limit the scope of an action to specific place, content type, or content item.
By default, missions you create can take place anywhere in the community. You can use metadata to ensure users take actions in a specific place, or on a specific item. For example, you might want users to complete an R&D mission by posting content in a dedicated Design space, or you might want new users to collaborate on the latest Marketing plan to earn a badge for campaign contributions. Metadata consists of one or more name=value pairs that you specify in the Metadata line of each rule in a mission.