The Brief: Tool can be a slang term for "gun" or an insulting way to refer to a man or boy.

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As an insult, to call someone a tool means to call them lame, specifically if they have an inflated ego.

As a nickname for a gun, Tool is used often in rap music by artists such as Childish Gambino and A$AP Mob.

Tool on my waist, shades on my face
Money in the bank, make no mistake – A$AP Mob