  We construct smeared CFT operators which represent a scalar field in AdS
interacting with gravity. The guiding principle is micro-causality: scalar
fields should commute with themselves at spacelike separation. To O(1/N) we
show that a correct and convenient criterion for constructing the appropriate
CFT operators is to demand micro-causality in a three-point function with a
boundary Weyl tensor and another boundary scalar. The resulting bulk
observables transform in the correct way under AdS isometries and commute with
boundary scalar operators at spacelike separation, even in the presence of
metric perturbations.
