Reagent inventory

Reagents and consumables are lab resources, not study assets, so inventory is tracked lab-wide rather than per study. The inventory screen is a catalog of reagents, the lots received against them, and an append-only ledger of what each run consumed.

Catalog, lots, and the consumption ledger

Three layers make up the inventory (ADR-0016):

• A catalog of reagents and consumables — the named materials the lab uses.
• Lots received against a reagent, each with a lot number, expiry date, and on-hand quantity.
• A consumption ledger that records every draw from a lot. The ledger is append-only: usage is never edited away, only added to, and a lot’s on-hand quantity is the received amount minus everything the ledger has drawn.

Consumption is guarded. A draw is rejected if the lot is expired, quarantined, or discarded, or if it would over-draw the remaining quantity; a lot depletes to zero rather than going negative. Because the ledger links to the worksheet run that consumed it, a reagent lot and the assay results it produced are traceable to each other — see analytical testing.

Note

Inventory writes are audited to the global chain rather than a study chain, because reagents are not study-scoped, and the actions are authorized on an inventory.manage authority a user can hold in any study (ADR-0016). Par-level reorder alerts are not built yet — see the roadmap.