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If I pay an extra $100 every month, how much sooner will I pay it off and how much interest will I save?"},{"title":"Comparing loan term scenarios","prompt":"Run an amortization schedule for a $180,000 student loan consolidation at 4.5% over 20 years so I can see the monthly payment and total interest before I decide whether to refinance."}],"resultDescription":"A JSON object containing the computed monthly payment, total interest paid, total amount paid, payoff duration in months, a breakdown of the first 12 monthly payments (principal, interest, balance per month), a yearly summary array showing cumulative principal paid, interest paid, and remaining balance per year, plus optional fields for extra payment and savings when an extra payment is provided.","failureModes":["Missing required query parameters (principal, rate, or years) returns an error response","Non-numeric values for principal, rate, or years cause a computation error","Extremely large principal or interest values may produce unexpected results","Zero or negative principal/rate/years may return an error or nonsensical schedule","Payment gateway failure (x402) if USDC balance is insufficient returns a 402 status"],"whenToPreferThis":"Choose this endpoint when you need a complete loan amortization schedule with month-by-month and year-by-year breakdowns, especially when you also want to quantify the impact of extra monthly payments. 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