causal agent vs causal agency

causal agent and causal agency both are nouns.

Word	Noun	Adjective	Verb	Adverb
causal agent	Yes	No	No	No
causal agency	Yes	No	No	No

As nouns, causal agent and causal agency are synonyms defined as:

causal agent and causal agency: any entity that produces an effect or is responsible for events or results

Other synonyms of causal agent include cause.

causal agent (noun)	causal agency (noun)
any entity that produces an effect or is responsible for events or results	any entity that produces an effect or is responsible for events or results