Va. Code § 59.1-503.5: Terms to be specified

An agreement that is otherwise sufficiently definite to be a contract is not invalid because it leaves particulars of performance to be specified by one of the parties. If particulars of performance are to be specified by a party, the following rules apply:(1) Specification must be made in good faith and within limits set by commercial reasonableness.(2) If a specification materially affects the other party's performance but is not seasonably made, the other party:(A) is excused for any resulting delay in its performance; and(B) may perform, suspend performance, or treat the failure to specify as a breach of contract.2000, cc. 101, 996.