agent vs causal agent

agent and causal agent both are nouns.

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

As nouns, causal agent is a hypernym of agent; that is, causal agent is a word with a broader meaning than agent:

agent: an active and efficient cause; capable of producing a certain effect
causal agent: any entity that produces an effect or is responsible for events or results

Other hypernyms of agent include causal agency, cause.

As nouns, causal agent is a hypernym of agent; that is, causal agent is a word with a broader meaning than agent:

agent: a substance that exerts some force or effect
causal agent: any entity that produces an effect or is responsible for events or results

Other hypernyms of agent include causal agency, cause, substance.

agent (noun)	causal agent (noun)
the semantic role of the animate entity that instigates or causes the happening denoted by the verb in the clause	any entity that produces an effect or is responsible for events or results
an active and efficient cause; capable of producing a certain effect
a businessman who buys or sells for another in exchange for a commission
a representative who acts on behalf of other persons or organizations
any agent or representative of a federal agency or bureau
a substance that exerts some force or effect