This is the 12338th most frequent Russian word.
каков
"Каков" means "what kind of" or "what is (he/it) like."
Here, 'каков' is used to inquire about the nature or content of the plan for the day.
Каков план на сегодня?
What is the plan for today?
In this sentence, 'каков' refers to the characteristics or capabilities of a person when engaged in a task.
Каков он в деле?
What is he like in action?
Here, 'каков' is utilized to describe the essence or nature of the outcome.