Yes, calls within a number masking session are automatically recorded. Recordings are available in .mp3 or .wav format and are securely stored on Plivo's infrastructure. You have the option to disable recording by setting the record attribute to false.
As an added benefit, Plivo offers complimentary storage for these recordings for up to 90 days. Should you require extended storage, it is available for a nominal fee of $0.0004 per minute per month, after the initial 90-day period.