There could be instructions in place to specify only all lowercase or just use .toLowercase() when sending. Also there could be a specified format for phone num

There could be instructions in place to specify only all lowercase or just use .toLowercase() when sending. Also there could be a specified format for phone numbers or a function that turns all input into the desired format by stripping all special characters. Possibly only hashing the last 9 digits of the phone number for non mission critical applications instead of the full 10 digits. This sounds like a good use case for short brief documentation.