Solution (source code)

= Solution

For an adjunction $F\dashv U:\mathcal D\to\mathcal C$ with induced monad $T=UF$, the <Eilenberg-Moore comparison functor> is
$$
K:\mathcal D\to\mathcal C^T,\qquad
K(D)=(UD,U\varepsilon_D).
$$
The adjunction is <monadic adjunction>[monadic] when $K$ is an equivalence.

The <Crude monadicity theorem> states that a right adjoint is monadic if it reflects isomorphisms, its source has coequalizers of reflexive pairs, and it preserves those coequalizers. The dual statement is the crude comonadicity theorem.