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Non-comonad cohomology?

For each algebraic theory, there is an adjunction, and therefore a (co)monad (or called a (co)triple. A comonad is a special comonoid, so by a universal property of $\Delta^{op}$ we get a cosimplicial object (the Bar construction [1]).

From this, one derives a cohomology theory of this algebraic theory. This subsumes group cohomology, Lie algebra cohomology, Hochschild cohomology, and Harrison's cohomology for commutative algebras [2, chapter 6+7].

Question

  1. What cohomology theories are known to not from comonads?
  2. Thinking of a group as a category with one object, this line of thoughts fits naturally into. Does it has an analogy to higher categories too?

Reference

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