Leftover/Freshness Countdown Tracker implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t7-074

Effect

Computation or source lookup only

Input and validation requirements

The instrument cannot produce a deterministic numeric result from the supplied specification because the required FoodSafety.gov/USDA shelf-life lookup table is absent and the table may contain ranges rather than one shelf-life value. It also lacks an explicit date-range and overflow policy; a positive shelf life added to 9999-12-31 produces an out-of-range date.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "food_item": "cooked meat or poultry leftovers",
    "date_stored": "2025-03-01",
    "storage_method": "fridge",
    "today": "2025-03-05"
  },
  "expected_outputs": {
    "estimated_use_by_date": "2025-03-05",
    "days_remaining": 0
  },
  "reference_data": {
    "foodkeeper_table_row": {
      "food_item": "cooked meat or poultry leftovers",
      "storage_method": "refrigerator",
      "shelf_life": "3–4 days"
    },
    "selected_shelf_life_days": 4,
    "selection_policy": "maximum endpoint of the USDA range",
    "source_convention": "USDA FoodKeeper / FoodSafety.gov standard consumer food-storage table value"
  },
  "working": "1. Select 4 days from the table's 3–4 day refrigerator range using the stated maximum-endpoint policy. 2. 2025-03-01 + 4 calendar days = 2025-03-05. 3. days_left = 2025-03-05 − 2025-03-05 = 0 days."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche7/tranche7-results.json