A method can include asynchronously receiving a well trajectory as part of a well plan, a fluid plan as part of the well plan and a bottom hole assembly plan as part of the well plan where the well trajectory is based at least in part on information associated with a geologic environment; asynchronously determining coherency metrics as to dependencies between the well trajectory, the fluid plan and the bottom hole assembly plan; and, based at least in part on the coherency metrics, issuing one or more messages that call for adjusting one or more of the well trajectory, the fluid plain and the bottom home assembly plan.