json to keyframes

i'm looking for a way to create a set of keyframes from data in a json file. i want to do this to fine tune the position of the keyframes in the timeline.

i can use the "convert expression to keyframes" function but that seems to create a keyframe for every frame. is there a way i can specifically create keyframes from the json? for instance, if the json contained a frame index, to only create keyframes on specific frames?