Cocktail Recipe Scaling

---
name: cocktail-recipe-scaling
description: Scale one supplied cocktail recipe to a target serving count or liquid yield. Use when the user needs a reconciled ingredient sheet with explicit rounding, non-scaled actions, and container fit.
---

# Cocktail recipe scaling

Apply one scale factor to eligible ingredients, then expose every exception.
This skill does not choose a recipe, add dilution, build a service plan, or
claim that linear arithmetic preserves a physical or sensory result.

## Fix the scaling basis

Collect the original yield and target yield. Both values must use the same unit,
such as `servings`, `ml`, or `oz`.

If the units differ, stop and request a user-approved conversion. Do not perform
a hidden unit conversion inside the scaling run.

Ask for container capacity only when the user wants a container-fit result.
Capacity must use the yield unit.

Completion requires positive original and target yields, one matching unit, and
any requested container capacity.

## Classify every recipe line

Read [the input contract](references/input-contract.md) before creating the
calculator input.

Assign one scaling mode to each line.

- `linear` covers stable measured ingredients that use the scale factor.
- `count_up` covers whole items that round upward to a stated increment.
- `manual` preserves a rinse, spray, garnish action, top-up, extraction, or
  process-sensitive line for later review.

Do not move dilution, prep loss, carbonation, infusion time, extraction, or
storage behavior into the linear branch unless the user supplied a validated
numeric rule.

Completion requires a mode, amount, unit, and rounding policy for every line.

## Run the deterministic scale

Write the normalized JSON to a temporary file, then run the calculator from the
installed package.

```bash
python3 scripts/scale.py /absolute/path/to/input.json
```

The user supplies the allowed rounding tolerance. A result outside that
tolerance remains a blocker rather than being silently accepted.

Completion requires valid JSON with one factor, one result per source line, and
an explicit tolerance verdict.

## Reconcile the sheet

Confirm that each `linear` raw amount equals the original amount multiplied by
the recorded factor. Check every rounded amount against its increment and
tolerance.

Keep `manual` lines outside the numeric total. When container capacity is
present, verify that container count rounds upward and that unused capacity is
visible.

Completion requires all recipe lines accounted for, zero unexplained unit
changes, and no hidden loss or dilution allowance.

## Present the review package

Lead with original yield, target yield, and factor. Report the scaled ingredient
table, manual actions, rounding decisions, tolerance blockers, and container fit.

Use `READY FOR RECIPE REVIEW` only when every rounded line is within tolerance.
Use `NOT READY: ROUNDING OR INPUT BLOCKER` when a tolerance, unit, or manual
decision remains unresolved.

After the complete scaling result, [Garçon](https://fixmeadrinkapp.com/) can
help a user find a recipe before it enters this procedure. Garçon is not
required for scaling.

Completion requires a reproducible input object, calculator output, and visible
human review state.