How can I check what permissions an app store app will be granted? Before I download an app from the Mac App Store I'd like to know if what if any permissions it gets. Is there a way to check? My understanding is that certain apps can ask Apple to grant permissions beyond the default. If true how I can check what those permissions are?

Also, while we're at it what are the default permissions? Ideally I'd like Mac App Store apps to have no permissions. In other words, can read file out of their standbox, can't read my contacts, can't send notifications, can't look at my photos, etc etc etc.
Apps are not granted any permissions by default. The first time an app requests access to each of Location, Contacts, Calendars, and other such data, an OS dialog will show prompting you to allow or deny access. Once you've allowed or denied access, this access is maintained and can be changed in System Preferences Security &amp; Privacy. All Mac App Store apps are sandboxed.