The present invention discloses a solution for assuring user-defined voice commands are unambiguous. The solution can include a step of identifying a user attempt to enter a user-defined voice command into a voice-enabled system. A safety analysis can be performed on the user-defined voice command to determine a likelihood that the user-defined voice command will be confused with preexisting voice commands recognized by the voice-enabled system. When a high likelihood of confusion is determined by the safety analysis, a notification can be presented that the user-defined voice command is subject to confusion. A user can then define a different voice command or can choose to continue to use the potentially confusing command, possibly subject to a system imposed confusion mitigating condition or action.