Is there a way to add "Credit Score" to the "Trends" tab? Users should be told to record their monthly "score" if historical data will not be available past 30 days.
If you can get monthly updates on one's credit score, it would stand to reason that the information presented to the user would be stored on Mint. If Mint has the information stored, it would be fair to either make the information available to the user without limitation OR inform the user that the information will only be available for a specified limited period of time.
Many other services that provide 'free credit scores' (e.g. CapitalOne's CreditWise, AMEX's FICOScore) also provide trend charts that show the user's monthly credit scores.