In one embodiment, a method includes receiving a natural-language message including an authorization request to authorize a first user access to one or more of a number of connected devices associated with a second user; parsing the natural-language message; identifying, based on the parsed natural-language message, the first user and one or more of a number of connected devices; implicitly determining that the first user is authorized to access the identified one or more of the number of connected devices based on a calculated strength of a relationship between a node representing the first user in a social graph and a node representing the second user in the social graph satisfying a pre-determined threshold; and providing, based on the implicit authorization, access to the identified one or more of the number of connected devices.