Final answer:
In MyChart, the masterfile where you specify how close to today and how far into the future a visit type can be scheduled is called the appointment scheduling rules masterfile.
Step-by-step explanation:
In MyChart, the masterfile where you would specify how close to today and how far into the future a visit type can be scheduled is called the appointment scheduling rules masterfile. This masterfile allows administrators to set parameters for appointment scheduling, including the maximum and minimum time frames for future appointments. By adjusting these settings, the system can ensure that visits can only be scheduled within a specific range of dates.