# Cost optimization ## What this pack lets workers do A collection of nouns and verbs for finding and measuring cost savings without breaking anything. Workers build a ledger from usage exports and invoices you supply, read dated public prices, propose savings with their arithmetic and risks, measure the promising ones before and after, and recommend changes for you to make. Billed, measured, estimated and credit amounts never get mixed, and unknown amounts stay unknown. ## Nouns | Noun | What it holds | | --- | --- | | Method | Four kinds of numbers kept apart, dated prices, nulls not zeros, quality must hold, the caller's model settings kept | | Templates | Cost ledger, price card (with a synthetic example), saving hypothesis, saving result, recommendation and review | ## Verbs | Verb | What the worker does | Produces | | --- | --- | --- | | inventory-costs | One ledger line per service and unit, with its source | Cost ledger | | price-check | Reads public pricing pages; never logs in | Price cards | | propose-savings | Concrete savings with arithmetic and risks, and the measurements they need | Saving hypotheses | | measure-saving | Before and after, two runs each, locally, with committed pass marks | Saving result | | recommend | Do, measure first or no change, with trade-offs | Recommendation | | review-recommendation | A different worker recomputes every saving | Review | Each verb can also end with `no_change`, `unknown` or `blocked`. Measurements follow the [evaluation-design](../evaluation-design/README.md) method. ## How to use it Write usage exports or invoices as nouns. Write the nouns in [nouns.json](nouns.json) create-only with a key scoped to your team's surface, then fill a template from [verbs.json](verbs.json) with `scripts/build_packs.py --instantiate