Connotations

Instrument and Tool:
The definition of a tool is an implement, especially one held in the hand, as a hammer, saw, or file, for performing or facilitating mechanical operations. When the definition of an instrument is a mechanical tool or implement, especially one used for delicate or precision work. So they are both implements but the instrument is used for more precise work such as surgical operations, but the tool is used for more mechanical operations. A time you would use a tool is when you are building a house you might use a hammer or saw. A time someone would use an instrument is when you are at the dentist and they clean our teeth with the metal pick instrument and also the small mirror insturment.