It was said in the manga a couple of times. In combat, he has the intuition of a prankster, because that's all he did growing up.
In battle, he can analyze the situation pretty well too. During the Pain fight,
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. He doesn't actually need Kurama or the frogs or whomever to analyze battles. He could have probably figured out Shinra Tensei on his own.
Hell, during the VOTE2 fight, Kurama's role was less to advise Naruto and more to explain the balance between Sasuke and Naruto, as well as to be Sasuke's hype-man xD