Scout is about the size of a small cooler and it trundles along at walking pace. Amazon claims the battery-powered robot can safely deal with obstacles such as pedestrians and pets. However, it's not yet clear how Scout verifies customers' identity to make sure its storage hatch opens only for the correct people.

Amazon is far from the only company working on delivery robots, though the e-commerce giant's expansive ecosystem could give Scout more of an advantage over rival robots. It's not unlikely that Scout, or future versions of it, will work with Key, which opens your door (and soon your garage) to let couriers drop off packages inside your house when you're not there. For the time being, at least, it seems you'll have to be home to receive a package from Scout when it stops by.