organic chemistry - Is hydronium an electrophile, nucleophile, both or neither?

Is hydronium an electrophile or a nucleophile? I expected $\ce{H3O+}$ to be a nucleophile due to the presence of electrons in the $\ce{2p}$ orbitals of $\ce{O}$. But the answer key of the test states that its none of them.

I can rationalise it this way: If $\ce{O}$ donates its 2 electrons then there would be 2 positive charges on $\ce{O}$ leading to instability.

But I am not too sure of my reasoning either. Isn't hydronium serving as a nucleophile in its reaction with $\ce{OH-}$ ? Why is it then neither an electrophile nor a nucleophile?

Google books results show that its mentioned as an electrophile in some books. While there's disagreement on other sides on the internet? What's the true classification?