Source: https://guthlabs.ai/docs/instruments/meal-prep-portion-calculator/mechanism/

instrument mechanism / verified-clean

# Meal Prep Portion Calculator mechanism

The inspectable method record for Meal Prep Portion Calculator, kept separate from implementation and qualification.

Status: **VERIFIED_CLEAN**Lifecycle: **verified-clean**

## Model scope

The formulas are standard and algebraically correct under the stated assumptions. NEEDS_REVIEW is required because the specification leaves the exact quantity type/unit, macro units and field schema, and validation constraints ambiguous. The honest label appropriately states that nutrition figures depend on user-supplied totals and are not from a certified nutrition database; it should also clarify that results are batch averages and assume uniform distribution.

No additional formula finding is recorded.

## Units and conventions

- total_qty is a numeric mass or volume with a stated unit, and the output preserves that unit unless an explicit conversion is requested

- num_portions is a positive integer

- Each total_macro value has a stated unit, such as kcal or grams, and is divided independently by num_portions

- Macro totals are user-supplied and represent the entire batch

## Inspectable vector

One of 4 source-bound review vectors:

````
{
  "inputs": {
    "total_qty": 2400,
    "total_qty_unit": "g",
    "num_portions": 6,
    "total_macros": {
      "calories": 3600,
      "protein_g": 180,
      "carbohydrates_g": 300,
      "fat_g": 120
    }
  },
  "expected_outputs": {
    "portion_qty": 400,
    "portion_qty_unit": "g",
    "per_portion_macros": {
      "calories": 600,
      "protein_g": 30,
      "carbohydrates_g": 50,
      "fat_g": 20
    }
  },
  "working": "portion_qty = 2400 g / 6 = 400 g. Calories = 3600 kcal / 6 = 600 kcal. Protein = 180 g / 6 = 30 g. Carbohydrates = 300 g / 6 = 50 g. Fat = 120 g / 6 = 20 g."
}
````

## Failure boundary

**BREAK_CLAIMED** · SELF_FLAGGED

The calculator reaches undefined results when num_portions is zero and should reject that input. A separate convention hazard exists when the total yield has no explicit unit, although the arithmetic remains numerically valid.

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/meal-prep-portion-calculator/>)[03**Implementation**](<https://guthlabs.ai/docs/instruments/meal-prep-portion-calculator/implementation/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/meal-prep-portion-calculator/qualification/>)

## Sources and evidence

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

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`

- `BOUNDARY_HAZARD_CATALOG.json`