inspect (object / person / me / here)
Attempts to use your character's intuition, experience and knowledge to generate more insight about the object's use, its condition, or its characteristics.
Inspecting a weapon may give you an idea of the characteristics of the item, its condition, what kind of round or bullet it takes, and anything else worthy of note.
Inspecting a person will give you a rough idea of their physical characteristics based on visible body areas. Beware that most people will not appreciate being started at.