how do i make an object look away from a face?

I am working on a test blend for a creature creation system and have encountered a problem. what I need is that when I add a part (in this case a spike) it needs to pointing away from the face that it was added on.

here is a simplified blend test post.blend (647 KB).

thanks for all the advice:) I’m still kinda new to scripting and have been learning as i go.

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