Fragment reference

A fragment answers one question about an item. Absence is the default: an item with no Stack fragment does not stack, and one with no Size fragment is one cell.

All of them are USTRUCTs deriving from FEDItemFragment, stored in a definition's Fragments array. None has virtual functions.

Core

Display

Name, description, icon, category label. What the UI reads.

Field	Type
Display Name	FText
Description	FText
Category	FText — the label, distinct from the definition's category tag
Icon	TSoftObjectPtr<UTexture2D> — streamed asynchronously

Stack

Field	Meaning
Stackable	Whether stacks merge at all
Max Stack Size	Units per stack
Maximum Quantity	Cap across the whole inventory. 0 = uncapped

Stacking also requires identical per-stack state and identical dynamic tags — see Items and fragments.

Size

Field	Meaning
Width / Height	Cells covered in a grid layout
Use Shape	Whether the occupancy mask applies
Occupancy Mask	Per-cell booleans for non-rectangular items

Rarity

Field	Meaning
Rarity Tag	The tier, e.g. Inventory.Rarity.Epic
Color	Accent colour used by slots and tooltips
Tier	A number, for sorting

Container Placement

Where the item wants to go. See Placement and routing.

Field	Meaning
Preferred Containers	Ordered tags; the first that accepts wins
Container Query	Containers the item tolerates at all

Nested Container

The item brings a container with it. See Nested containers.

Field	Meaning
Container Definition	The container it brings
Container Filter / Slot Filter	Where the item must be for it to be open
Content Policy	Whether the contents belong to the item and travel with it (Travel With Item, default) or to the carrier (Move To Owner)

Prerequisites

Conditions checked before a container accepts the item, reported as player-readable text.

Prerequisite	Checks
Required Item	Another item is held, or forbidden — bForbidden inverts it
Required Attribute (GAS)	A GAS attribute against a threshold

Stat Rolls

Stats decided when the item is created rather than authored. Rolled once on the server, stored in the entry's state.

Field	Meaning
Rolls	Per-stat tag, range and roll mode
Roll Mode	Uniform, weighted toward the middle, and so on

World Model

How the item looks on the ground. See Items in the world.

Field	Meaning
Model Type	Static mesh, skeletal mesh or actor class
Mesh / Actor Class	What to show
Override Material	Per-item material override
Offset / Rotation / Scale	Resting transform
Simulate Physics	Whether it falls

Grants (GAS)

Effects, abilities and attribute sets granted while the item is somewhere, doing something. See Gameplay Ability System.

Field	Meaning
Effect Grants	Effect + condition + level
Ability Grants	Ability + condition + level
Attribute Set Grants	Attribute set + condition

Every grant carries the same condition and level:

Field	Meaning
Container / Slot Filter	Where the item is kept, and on which peg
State Filter	What it is DOING there — Inventory.Equipment.State.Held. Usually the one you want
Level Source	Fixed (the number here) or Item State (a per-instance counter)
Level State Tag	Which counter, when the level comes from the item
Stack Mode	Once, or Per Unit for things that add up

Each condition carries a Container Filter and a Slot Filter.

Equipment module

Equipment

Everything about an item as equipment: the slot it belongs in, and how it behaves and appears in each state it can be in. See Equipment.

Field	Meaning
Equip Slot	The slot tag this item is worn in. Leave unset for something only ever held
States	One entry per state, first match wins

Each state carries:

Field	Meaning
State Tags	Which equipment states this covers. Empty means any state — what armour wants
Container / Slot Filter	Narrows it further, when the state alone is not specific enough
Visual Type	Static mesh, skeletal mesh or actor
Mesh / Skeletal Mesh / Actor Class	What to show
Follows Avatar Pose	Whether a skeletal piece uses the character's animation
Anim Class / Avatar Anim Layer	Animation for the piece
Material	Override
Attach Socket / Offset / Rotation / Scale	Fit, relative to the anchor
Attach Rule	Which component to attach to
Prerequisites	Conditions the state requires
No Model	The state is real but draws nothing — a ring, a passive charm

Other modules

Fragment	Module	Answers
Weight	Weight	Unit weight
Value	Trading	Base worth; without it an item cannot be sold
Usable	Usable	Use-effect tag, verb, consumption
Durability	Durability	Maximum durability and what happens at zero
Fuel	Crafting	How many seconds one unit burns for; without it an item is not fuel
Mutable Equipment	Equipment · Mutable	Customizable Object parameters to write while worn

Reading a fragment

// From a definition
if (const FEDStackFragment* Stack = Definition->FindFragment<FEDStackFragment>()) { ... }

// From an entry, resolving the definition on the way
if (const FEDStackFragment* Stack = UEDItemStatics::FindItemFragment<FEDStackFragment>(Entry)) { ... }

Get Fragment           (Definition, wildcard out) → Boolean
Has Fragment Of Type   (Definition, Struct)       → Boolean

The Blueprint Get Fragment node is a wildcard: pick the struct type on the output pin and it copies the first matching fragment, returning false and leaving the default if there is none.

One of each

At most one fragment of each type per definition. Asset validation flags duplicates, because the second one would silently never be read.

Where next

• Items and fragments
• Extending — writing your own