Agent

agens

(grammar: performer of the action in a sentence)

agent

(someone who works for an intelligence agency)

agent

(computing: part of the system that performs action on behalf of a client or server)

agentka

(someone who works for an intelligence agency)

czynnik

(active power or cause)

pełnomocnik

(law: one who acts in place of another)

plenipotent

(law: one who acts in place of another)

środek

(active power or cause)