If that's a valid review comment, "ok." is a valid response to it. Low effort comments get low effort responses. If you want to have a discussion, maybe poin

If that's a valid review comment, "ok." is a valid response to it. Low effort comments get low effort responses. If you want to have a discussion, maybe point out what you don't understand and what you expected. "I don't quite get this - I would expect this to use the existing pattern used in [file 1] and [file 2]. Would you mind walking me through your reasoning here?" can actually start a discussion, and isn't so adversarial.