{
  "tool_id": "art-221-llpa-stack",
  "kernel_id": "art-221-llpa-stack",
  "display_name": "LLPA Stack Calculator",
  "tool_version": "1.0.0",
  "mandate_type": "compliance_mandate",
  "purpose": "Fannie Mae public LLPA (Loan-Level Price Adjustment) matrix calculator. FICO-by-LTV base grid plus feature surcharges: cash-out refinance, second home, investment property, warrantable condo, subordinate financing. Applies FTHB AMI waiver (SEL-2023-07, up to 1.75 pp reduction for first-time buyers at or below 100% AMI). Table version: FNM-LLPA-2025-11-01 (Fannie Mae public publication). Not check_agency_eligibility_matrix (DU/LPA approval grid) or check_conforming_loan_limit (FHFA size limits).",
  "control_description": "Fannie Mae public LLPA (Loan-Level Price Adjustment) matrix calculator. FICO-by-LTV base grid plus feature surcharges: cash-out refinance, second home, investment property, warrantable condo, subordinate financing. Applies FTHB AMI waiver (SEL-2023-07, up to 1.75 pp reduction for first-time buyers at or below 100% AMI). Table version: FNM-LLPA-2025-11-01 (Fannie Mae public publication). Not check_agency_eligibility_matrix (DU/LPA approval grid) or check_conforming_loan_limit (FHFA size limits).",
  "declared_inputs": [
    "art-222-agency-eligibility-matrix"
  ],
  "declared_outputs": [],
  "kernel_digest": "sha256:7221a3468182a878ebf517663153a90e4973b4125fe3d77c8a44789898b785ad",
  "trust_label": "independently verified -- zkVM execution proof (risc0/groth16-bn254)",
  "data_vintage": "2026-07-10",
  "last_validated": "2026-07-10",
  "conformance_fixtures_vendored": true,
  "compute_proof_ready": "ready",
  "wave": 38,
  "source_url": "https://ainumbers.co/chaingraph/art-221-llpa-stack.html",
  "generated_at": "2026-07-25T20:02:55.601Z"
}