Chain Stages · Fork at Step 1 · 1 Decision Gate (§21.4) · 2 Branches

1 ROOT + FORK node §21.4 gate

Conforming Loan Limit Check art-223-conforming-loan-limit

Classifies conforming/super-conforming/jumbo status and surfaces loan_program (VA / FHA / Conventional / USDA) from input into the output payload. The §21.4 gate reads /loan_program to route: VA to the VA benefit calculator, all others to FHA MIP calculation.

△ Fork Gate: if /loan_program == "VA" → Branch A (VA) | else (default) → Branch B (FHA/other)

MCP Call · check_conforming_loan_limit

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "check_conforming_loan_limit",
    "arguments": {
      "loan_amount": 420000,
      "units": 1,
      "state": "TX",
      "loan_program": "VA"
    }
  },
  "id": 1
}

⇃ fork

A BRANCH A · VA node VA path

VA Funding Fee and Residual Income art-225-va-funding-fee-residual

Computes VA funding fee per 38 USC §3729 (first/subsequent use, down-payment tier table) and residual income per VA Pamphlet 26-7 Ch.4 Table 41A (region by family size). Handles disability exemption, IRRRL flat rate (0.50%), and 41% DTI residual review trigger.

MCP Call · compute_va_funding_fee_residual

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "compute_va_funding_fee_residual",
    "arguments": {
      "base_loan_amount": 420000,
      "down_payment_pct": 5.0,
      "loan_purpose": "purchase",
      "va_use_type": "first",
      "funding_fee_exempt": false,
      "family_size": 3,
      "state": "TX",
      "dti_pct": 38.0,
      "gross_monthly_income": 8500,
      "monthly_shelter_expenses": 2200
    }
  },
  "id": 2
}

B BRANCH B · FHA / Default node FHA path

FHA MIP Eligibility art-224-fha-mip-eligibility

Computes FHA mortgage insurance premium eligibility and cost per HUD Handbook 4000.1. UFMIP: 1.75% of base loan amount. Annual MIP grid by loan size vs $726,200 threshold, LTV, and term (ML 2023-05). MIP duration: 11 years if LTV at or below 90%; life-of-loan if above. Applies 31%/43% qualifying ratios and minimum FICO by LTV tier.

MCP Call · compute_fha_mip_eligibility

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "compute_fha_mip_eligibility",
    "arguments": {
      "base_loan_amount": 420000,
      "ltv_pct": 96.5,
      "term_years": 30,
      "fico_score": 640,
      "front_end_dti_pct": 28.5,
      "back_end_dti_pct": 41.0,
      "loan_purpose": "purchase"
    }
  },
  "id": 2
}

Mortgage Government Loan Fit