# AgentPMT Marketplace Product (Agent Format)

Name: Financial Loan Amortization Calculator
Product ID: 69858a60269243768b447d61
Vendor: Apoth3osis
Agent description: Use this tool for any loan math or mortgage calculation. Supports: calculate_payment (periodic payment amount), calculate_loan_principal (max borrowing from a target payment), calculate_term (payoff timeline), simple_interest, compound_interest (with optional recurring contributions), amortization_schedule (full table with downloadable CSV), compare_loans (rank scenarios by total cost, payment, or interest), affordability_analysis (max loan and home price from income and debts), refinance_break_even (savings, break-even months, net benefit), payoff_acceleration (interest and term savings from extra payments), and rate_conversion (nominal APR to effective annual and per-period rates). All actions accept standard loan parameters: principal, annual_rate, years. Send {"action": "get_instructions"} for full parameter documentation and examples.
Price: 500 credits

External Agent API:
- Docs: https://www.agentpmt.com/external-agent-api
- Purchase credits: POST https://www.agentpmt.com/api/external/credits/purchase
- Create session: POST /api/external/auth/session
- Balance: POST https://www.agentpmt.com/api/external/credits/balance
- Invoke this tool: POST https://www.agentpmt.com/api/external/tools/69858a60269243768b447d61/invoke
- Workflows: GET https://www.agentpmt.com/api/external/workflows
- Workflow fetch: POST https://www.agentpmt.com/api/external/workflows/{workflowId}/fetch
- Workflow start: POST https://www.agentpmt.com/api/external/workflows/{workflowId}/start
- Workflow end: POST https://www.agentpmt.com/api/external/workflows/{workflowId}/end
- Workflow active: POST https://www.agentpmt.com/api/external/workflows/active
- Jobs list: POST https://www.agentpmt.com/api/external/jobs/list
- Job reserve: POST https://www.agentpmt.com/api/external/jobs/{jobId}/reserve
- Job complete: POST https://www.agentpmt.com/api/external/jobs/{jobId}/complete
- Job status: POST https://www.agentpmt.com/api/external/jobs/{jobId}/status
- Job workflow create: POST https://www.agentpmt.com/api/external/jobs/{jobId}/workflow/create
- Job workflow update: PUT https://www.agentpmt.com/api/external/jobs/{jobId}/workflow/{workflowId}
- Job workflow publish (private): POST https://www.agentpmt.com/api/external/jobs/{jobId}/workflow/{workflowId}/publish

Categories: Scientific Computing, Financial Modeling, Financial Data, Percentage & Ratio Calculators, Finance & Accounting, Risk Management & Analytics

```json
{
  "actions": {
    "calculate_payment": {
      "description": "Compute the periodic payment for an amortizing loan. Supports interest-only periods, balloon payments, and configurable payment/compounding frequencies.",
      "properties": {
        "principal": {
          "type": "number",
          "description": "Loan principal amount",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Nominal annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "years": {
          "type": "number",
          "description": "Loan term in years",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "payments_per_year": {
          "type": "integer",
          "description": "Payment frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "future_value": {
          "type": "number",
          "description": "Target future value after final payment",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "balloon_payment": {
          "type": "number",
          "description": "Balloon amount due at maturity",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "interest_only_periods": {
          "type": "integer",
          "description": "Number of interest-only payment periods at the start",
          "required": false,
          "default": 0,
          "minimum": 0
        }
      }
    },
    "calculate_loan_principal": {
      "description": "Calculate the maximum loan principal supported by a given periodic payment amount.",
      "properties": {
        "payment_amount": {
          "type": "number",
          "description": "Periodic payment amount",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Nominal annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "years": {
          "type": "number",
          "description": "Loan term in years (provide years or target_periods or both)",
          "required": false,
          "minimum": 0,
          "maximum": 100
        },
        "target_periods": {
          "type": "integer",
          "description": "Target number of payment periods (alternative to years)",
          "required": false,
          "minimum": 1,
          "maximum": 12000
        },
        "payments_per_year": {
          "type": "integer",
          "description": "Payment frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "future_value": {
          "type": "number",
          "description": "Target future value",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "balloon_payment": {
          "type": "number",
          "description": "Balloon due at maturity",
          "required": false,
          "default": 0,
          "minimum": 0
        }
      }
    },
    "calculate_term": {
      "description": "Calculate the number of periods and years required to pay off a loan given principal, rate, and payment amount.",
      "properties": {
        "principal": {
          "type": "number",
          "description": "Loan principal",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Nominal annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "payment_amount": {
          "type": "number",
          "description": "Periodic payment amount",
          "required": true,
          "minimum": 0
        },
        "payments_per_year": {
          "type": "integer",
          "description": "Payment frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        }
      }
    },
    "simple_interest": {
      "description": "Calculate simple (non-compounded) interest totals for a given principal, rate, and duration.",
      "properties": {
        "principal": {
          "type": "number",
          "description": "Principal amount",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "years": {
          "type": "number",
          "description": "Duration in years",
          "required": true,
          "minimum": 0,
          "maximum": 100
        }
      }
    },
    "compound_interest": {
      "description": "Calculate compound interest growth over time, optionally with periodic contributions. Supports configurable compounding frequency and contribution timing.",
      "properties": {
        "principal": {
          "type": "number",
          "description": "Initial principal amount",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "years": {
          "type": "number",
          "description": "Investment duration in years",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "periodic_contribution": {
          "type": "number",
          "description": "Amount added each contribution period",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "contribution_frequency_per_year": {
          "type": "integer",
          "description": "How often contributions are made per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "contribution_timing": {
          "type": "string",
          "description": "Whether contribution is made at period end or beginning",
          "required": false,
          "default": "end",
          "enum": [
            "end",
            "beginning"
          ]
        }
      }
    },
    "amortization_schedule": {
      "description": "Build a full amortization table with support for extra payments, one-time lump sums, interest-only periods, balloon payments, and optional CSV file export to cloud storage.",
      "properties": {
        "principal": {
          "type": "number",
          "description": "Loan principal",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Nominal annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "years": {
          "type": "number",
          "description": "Loan term in years",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "payments_per_year": {
          "type": "integer",
          "description": "Payment frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "future_value": {
          "type": "number",
          "description": "Target future value",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "balloon_payment": {
          "type": "number",
          "description": "Balloon due at maturity",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "interest_only_periods": {
          "type": "integer",
          "description": "Interest-only period count",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "extra_payment": {
          "type": "number",
          "description": "Recurring extra principal each period",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "extra_payment_start_period": {
          "type": "integer",
          "description": "Period to begin recurring extra payments",
          "required": false,
          "default": 1,
          "minimum": 1
        },
        "one_time_extra_payments": {
          "type": "array",
          "description": "List of one-time extra principal payments",
          "required": false,
          "items": {
            "type": "object",
            "properties": {
              "period": {
                "type": "integer",
                "description": "Payment period index (1-based)",
                "required": true,
                "minimum": 1
              },
              "amount": {
                "type": "number",
                "description": "Extra principal payment amount",
                "required": true,
                "minimum": 0
              }
            }
          }
        },
        "start_date": {
          "type": "string",
          "description": "Schedule start date in YYYY-MM-DD format; adds date column to each row",
          "required": false
        },
        "return_schedule": {
          "type": "boolean",
          "description": "Include schedule rows in response",
          "required": false,
          "default": true
        },
        "max_schedule_rows": {
          "type": "integer",
          "description": "Maximum amortization rows to return",
          "required": false,
          "default": 5000,
          "minimum": 1,
          "maximum": 50000
        },
        "store_schedule_file": {
          "type": "boolean",
          "description": "Upload schedule as CSV to cloud storage and return file metadata",
          "required": false,
          "default": false
        },
        "expiration_days": {
          "type": "integer",
          "description": "Cloud file expiration in days",
          "required": false,
          "default": 7,
          "minimum": 1,
          "maximum": 7
        }
      }
    },
    "compare_loans": {
      "description": "Compare multiple loan scenarios side-by-side and rank by selected metric (lowest payment, lowest interest, or lowest total cost).",
      "properties": {
        "compare_scenarios": {
          "type": "array",
          "description": "Loan scenarios to compare (minimum 2 required)",
          "required": true,
          "items": {
            "type": "object",
            "properties": {
              "name": {
                "type": "string",
                "description": "Scenario label",
                "required": true
              },
              "principal": {
                "type": "number",
                "description": "Loan principal",
                "required": true,
                "minimum": 0
              },
              "annual_rate": {
                "type": "number",
                "description": "Annual rate in percent",
                "required": true,
                "minimum": 0,
                "maximum": 100
              },
              "years": {
                "type": "number",
                "description": "Term in years",
                "required": true,
                "minimum": 0,
                "maximum": 100
              },
              "payments_per_year": {
                "type": "integer",
                "description": "Payments per year",
                "required": false,
                "default": 12,
                "minimum": 1,
                "maximum": 365
              },
              "compounding_per_year": {
                "type": "integer",
                "description": "Compounding per year",
                "required": false,
                "default": 12,
                "minimum": 1,
                "maximum": 365
              },
              "extra_payment": {
                "type": "number",
                "description": "Recurring extra principal per payment",
                "required": false,
                "default": 0,
                "minimum": 0
              },
              "balloon_payment": {
                "type": "number",
                "description": "Balloon due at maturity",
                "required": false,
                "default": 0,
                "minimum": 0
              },
              "interest_only_periods": {
                "type": "integer",
                "description": "Interest-only period count",
                "required": false,
                "default": 0,
                "minimum": 0
              }
            }
          }
        },
        "comparison_metric": {
          "type": "string",
          "description": "How to rank scenarios",
          "required": false,
          "default": "lowest_total_cost",
          "enum": [
            "lowest_payment",
            "lowest_interest",
            "lowest_total_cost"
          ]
        }
      }
    },
    "affordability_analysis": {
      "description": "Estimate affordable monthly payment, maximum loan principal, and maximum home price based on income, debts, and DTI ratios.",
      "properties": {
        "annual_income": {
          "type": "number",
          "description": "Gross annual income",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Expected mortgage rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "years": {
          "type": "number",
          "description": "Loan term in years",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "monthly_debts": {
          "type": "number",
          "description": "Recurring monthly debt obligations",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "monthly_expenses": {
          "type": "number",
          "description": "Additional recurring monthly expenses",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "front_end_ratio": {
          "type": "number",
          "description": "Maximum housing expense ratio to gross income",
          "required": false,
          "default": 0.28,
          "minimum": 0,
          "maximum": 1
        },
        "back_end_ratio": {
          "type": "number",
          "description": "Maximum total debt ratio to gross income",
          "required": false,
          "default": 0.36,
          "minimum": 0,
          "maximum": 1
        },
        "property_tax_monthly": {
          "type": "number",
          "description": "Estimated monthly property tax",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "insurance_monthly": {
          "type": "number",
          "description": "Estimated monthly insurance",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "hoa_monthly": {
          "type": "number",
          "description": "Estimated monthly HOA fees",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "down_payment": {
          "type": "number",
          "description": "Down payment amount (added to max principal for max home price)",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "payments_per_year": {
          "type": "integer",
          "description": "Payment frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        }
      }
    },
    "refinance_break_even": {
      "description": "Estimate payment savings, break-even period, and net lifetime benefit of refinancing a loan.",
      "properties": {
        "current_balance": {
          "type": "number",
          "description": "Current remaining loan balance",
          "required": true,
          "minimum": 0
        },
        "current_rate": {
          "type": "number",
          "description": "Current annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "current_remaining_term_months": {
          "type": "integer",
          "description": "Remaining months on current loan",
          "required": true,
          "minimum": 1,
          "maximum": 1200
        },
        "new_rate": {
          "type": "number",
          "description": "New annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "new_term_months": {
          "type": "integer",
          "description": "New loan term in months",
          "required": true,
          "minimum": 1,
          "maximum": 1200
        },
        "closing_costs": {
          "type": "number",
          "description": "Refinance closing costs",
          "required": true,
          "minimum": 0
        },
        "current_payment": {
          "type": "number",
          "description": "Current monthly payment (if omitted, calculated automatically from balance/rate/term)",
          "required": false,
          "minimum": 0
        }
      }
    },
    "payoff_acceleration": {
      "description": "Model interest and term savings from recurring and one-time extra payments by comparing baseline vs accelerated payoff scenarios.",
      "properties": {
        "principal": {
          "type": "number",
          "description": "Loan principal",
          "required": true,
          "minimum": 0
        },
        "annual_rate": {
          "type": "number",
          "description": "Nominal annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "years": {
          "type": "number",
          "description": "Original loan term in years",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "payments_per_year": {
          "type": "integer",
          "description": "Payment frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "extra_payment": {
          "type": "number",
          "description": "Recurring extra principal each period",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "extra_payment_start_period": {
          "type": "integer",
          "description": "Period to begin recurring extra payments",
          "required": false,
          "default": 1,
          "minimum": 1
        },
        "one_time_extra_payments": {
          "type": "array",
          "description": "One-time extra payments",
          "required": false,
          "items": {
            "type": "object",
            "properties": {
              "period": {
                "type": "integer",
                "description": "Payment period index (1-based)",
                "required": true,
                "minimum": 1
              },
              "amount": {
                "type": "number",
                "description": "Extra principal payment amount",
                "required": true,
                "minimum": 0
              }
            }
          }
        },
        "future_value": {
          "type": "number",
          "description": "Target future value",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "balloon_payment": {
          "type": "number",
          "description": "Balloon due at maturity",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "interest_only_periods": {
          "type": "integer",
          "description": "Interest-only period count",
          "required": false,
          "default": 0,
          "minimum": 0
        },
        "start_date": {
          "type": "string",
          "description": "Optional start date in YYYY-MM-DD format",
          "required": false
        }
      }
    },
    "rate_conversion": {
      "description": "Convert a nominal annual percentage rate (APR) into effective annual, payment-period, and daily effective rates.",
      "properties": {
        "annual_rate": {
          "type": "number",
          "description": "Nominal annual interest rate in percent",
          "required": true,
          "minimum": 0,
          "maximum": 100
        },
        "compounding_per_year": {
          "type": "integer",
          "description": "Compounding frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        },
        "payments_per_year": {
          "type": "integer",
          "description": "Payment frequency per year",
          "required": false,
          "default": 12,
          "minimum": 1,
          "maximum": 365
        }
      }
    }
  },
  "properties": {
    "action": {
      "type": "string",
      "description": "Action to perform",
      "required": true,
      "default": "calculate_payment",
      "enum": [
        "get_instructions",
        "calculate_payment",
        "calculate_loan_principal",
        "calculate_term",
        "simple_interest",
        "compound_interest",
        "amortization_schedule",
        "compare_loans",
        "affordability_analysis",
        "refinance_break_even",
        "payoff_acceleration",
        "rate_conversion"
      ]
    },
    "principal": {
      "type": "number",
      "description": "Principal or present value",
      "required": false,
      "minimum": 0
    },
    "annual_rate": {
      "type": "number",
      "description": "Nominal annual interest rate in percent",
      "required": false,
      "minimum": 0,
      "maximum": 100
    },
    "years": {
      "type": "number",
      "description": "Loan term in years",
      "required": false,
      "minimum": 0
    },
    "payments_per_year": {
      "type": "integer",
      "description": "Payment frequency per year",
      "required": false,
      "default": 12,
      "minimum": 1,
      "maximum": 365
    },
    "compounding_per_year": {
      "type": "integer",
      "description": "Compounding frequency per year",
      "required": false,
      "default": 12,
      "minimum": 1,
      "maximum": 365
    },
    "payment_amount": {
      "type": "number",
      "description": "Periodic payment amount",
      "required": false,
      "minimum": 0
    },
    "target_periods": {
      "type": "integer",
      "description": "Target number of payment periods",
      "required": false,
      "minimum": 1
    },
    "future_value": {
      "type": "number",
      "description": "Target future value",
      "required": false,
      "minimum": 0
    },
    "balloon_payment": {
      "type": "number",
      "description": "Balloon due at maturity",
      "required": false,
      "minimum": 0
    },
    "interest_only_periods": {
      "type": "integer",
      "description": "Interest-only period count",
      "required": false,
      "minimum": 0
    },
    "extra_payment": {
      "type": "number",
      "description": "Recurring extra principal amount",
      "required": false,
      "minimum": 0
    },
    "extra_payment_start_period": {
      "type": "integer",
      "description": "Period to begin recurring extra payment",
      "required": false,
      "default": 1,
      "minimum": 1
    },
    "one_time_extra_payments": {
      "type": "array",
      "description": "One-time extra principal payments",
      "required": false,
      "items": {
        "type": "object",
        "properties": {
          "period": {
            "type": "integer",
            "minimum": 1
          },
          "amount": {
            "type": "number",
            "minimum": 0
          }
        },
        "required": [
          "period",
          "amount"
        ]
      }
    },
    "start_date": {
      "type": "string",
      "description": "Optional schedule start date in YYYY-MM-DD format",
      "required": false
    },
    "return_schedule": {
      "type": "boolean",
      "description": "Include schedule rows in response",
      "required": false,
      "default": true
    },
    "store_schedule_file": {
      "type": "boolean",
      "description": "Upload schedule CSV and return file metadata",
      "required": false
    },
    "max_schedule_rows": {
      "type": "integer",
      "description": "Maximum amortization rows to return",
      "required": false,
      "default": 5000,
      "minimum": 1,
      "maximum": 50000
    },
    "expiration_days": {
      "type": "integer",
      "description": "Cloud file expiration in days",
      "required": false,
      "default": 7,
      "minimum": 1,
      "maximum": 7
    },
    "periodic_contribution": {
      "type": "number",
      "description": "Contribution amount for compound interest projections",
      "required": false,
      "minimum": 0
    },
    "contribution_frequency_per_year": {
      "type": "integer",
      "description": "Contribution frequency per year",
      "required": false,
      "default": 12,
      "minimum": 1,
      "maximum": 365
    },
    "contribution_timing": {
      "type": "string",
      "description": "Contribution timing",
      "required": false,
      "default": "end",
      "enum": [
        "end",
        "beginning"
      ]
    },
    "compare_scenarios": {
      "type": "array",
      "description": "Scenarios for compare_loans",
      "required": false,
      "items": {
        "type": "object",
        "properties": {
          "name": {
            "type": "string"
          },
          "principal": {
            "type": "number",
            "minimum": 0
          },
          "annual_rate": {
            "type": "number",
            "minimum": 0,
            "maximum": 100
          },
          "years": {
            "type": "number",
            "minimum": 0
          },
          "payments_per_year": {
            "type": "integer",
            "minimum": 1,
            "maximum": 365
          },
          "compounding_per_year": {
            "type": "integer",
            "minimum": 1,
            "maximum": 365
          },
          "extra_payment": {
            "type": "number",
            "minimum": 0
          },
          "balloon_payment": {
            "type": "number",
            "minimum": 0
          },
          "interest_only_periods": {
            "type": "integer",
            "minimum": 0
          }
        },
        "required": [
          "name",
          "principal",
          "annual_rate",
          "years"
        ]
      }
    },
    "comparison_metric": {
      "type": "string",
      "description": "Scenario ranking method",
      "required": false,
      "default": "lowest_total_cost",
      "enum": [
        "lowest_payment",
        "lowest_interest",
        "lowest_total_cost"
      ]
    },
    "annual_income": {
      "type": "number",
      "description": "Gross annual income",
      "required": false,
      "minimum": 0
    },
    "monthly_debts": {
      "type": "number",
      "description": "Recurring monthly debt obligations",
      "required": false,
      "minimum": 0
    },
    "monthly_expenses": {
      "type": "number",
      "description": "Additional recurring monthly expenses",
      "required": false,
      "minimum": 0
    },
    "front_end_ratio": {
      "type": "number",
      "description": "Housing ratio against gross income",
      "required": false,
      "default": 0.28,
      "minimum": 0,
      "maximum": 1
    },
    "back_end_ratio": {
      "type": "number",
      "description": "Total debt ratio against gross income",
      "required": false,
      "default": 0.36,
      "minimum": 0,
      "maximum": 1
    },
    "property_tax_monthly": {
      "type": "number",
      "description": "Monthly property tax",
      "required": false,
      "minimum": 0
    },
    "insurance_monthly": {
      "type": "number",
      "description": "Monthly insurance",
      "required": false,
      "minimum": 0
    },
    "hoa_monthly": {
      "type": "number",
      "description": "Monthly HOA fees",
      "required": false,
      "minimum": 0
    },
    "down_payment": {
      "type": "number",
      "description": "Down payment amount",
      "required": false,
      "minimum": 0
    },
    "current_balance": {
      "type": "number",
      "description": "Current loan balance for refinance",
      "required": false,
      "minimum": 0
    },
    "current_rate": {
      "type": "number",
      "description": "Current interest rate for refinance",
      "required": false,
      "minimum": 0,
      "maximum": 100
    },
    "current_remaining_term_months": {
      "type": "integer",
      "description": "Remaining months on current loan",
      "required": false,
      "minimum": 1
    },
    "current_payment": {
      "type": "number",
      "description": "Current monthly payment",
      "required": false,
      "minimum": 0
    },
    "new_rate": {
      "type": "number",
      "description": "New interest rate for refinance",
      "required": false,
      "minimum": 0,
      "maximum": 100
    },
    "new_term_months": {
      "type": "integer",
      "description": "New loan term in months for refinance",
      "required": false,
      "minimum": 1
    },
    "closing_costs": {
      "type": "number",
      "description": "Refinance closing costs",
      "required": false,
      "minimum": 0
    }
  }
}
```