inventory-economy · diff
git:20260912.9399f33 to git:20260913.3c614b8
27 added, 7 removed. Audit A to A.
---
name: inventory-economy
- description: Generic bag rules. Slots are difficulty. Use with equipment-progression and durability-economy.
+ description: Use when carried items, stacks, unique slots, weight, pages, hotbars, pickup overflow, or discard behavior creates lost items, duplicate ownership, unclear capacity, or unusable inventory pressure.
---
- # Inventory economy
+ # Inventory Economy
- Ask: stack-tabs | unique-slots | weight | page-grid.
- Expanding the bag is a reward. Discard must be cheap to do and expensive in meaning.
- Replace (equipment A) wants many unique slots. Tree (B) wants fewer, heavier items.
- Hotbar ≤ what fingers can hit in combat. The rest is the pause bag.
+ This skill owns **inventory identity, capacity, stacking, containment, overflow and transfer rules**. `equipment-progression` owns item growth; `durability-economy` owns wear; `currency-dual` owns wallets.
- Accept: a full bag forces a real choice before the next pickup.
+ ## Modes
+
+ | Mode | Capacity model |
+ |---|---|
+ | stack-tabs | categories plus stack limits |
+ | unique-slots | one instance per occupied slot |
+ | weight | capacity derived from authored weight rules |
+ | page-grid | page/cell capacity and placement |
+
+ Capacity pressure is project data. A game may use meaningful scarcity, generous storage, auto-stash, unlimited quest inventory, or no discard at all. Do not force every full bag to become a dramatic choice.
+
+ ## Identity and transactions
+
+ Every item instance or stack has a stable ID/type identity and explicit quantity. Pickup, split, merge, move, equip, drop, discard and stash are transactions: either the source/destination state commits consistently or the operation fails without duplicating/losing items.
+
+ Publish stack-key rules, capacity calculation, reserved/quest-item policy and transfer ownership. Repeated pickup callbacks use a stable pickup/transaction ID when duplication is possible.
+
+ Overflow behavior is explicit: reject, leave in world, partial pickup, overflow queue, mail/stash, replace prompt, or another project-defined policy. Never silently delete the excess.
+
+ Hotbar/quick access is an input/UI policy layered on inventory. Its size and device mapping come from `input-design` and UI constraints, not a universal finger-count formula.
+
+ ## Acceptance
+
+ Test pickup at exact capacity, one-over capacity, stack merge/split, duplicate callback, move/equip interruption, save/reload and project-specific overflow. Item totals and stable identities remain explainable before and after every transaction. A full bag screenshot is not inventory evidence.