Between different carriers and states, the answer could be different.

The general rule is that you should disclose all drivers to your insurance company.

Typically, failure to disclose all licensed drivers, including those with a leaner's permit, who are residents of your household, and all accidents and violations attributable to any of these drivers, may result in voidance of coverage, policy cancellation, policy non-renewal or additional premium. Any person who knowingly and with intent to injure, defraud, or deceive any insurer, files a statement of claim or an application containing false, incomplete or misleading information, is guilty of a felony of the third degree (in Florida).

Okay, take a deep breath after reading all that...

Basically, all household residents must be listed or disclosed. It is up to state law and/or policy language to define a household resident. If a person is not a household resident (by definition) and you give them permission to drive then they should be covered by your policy.

The easiest way to verify is by calling your carrier and disclosing/asking their requirements.