Use when writing or debugging AActor and UActorComponent C++: constructor vs BeginPlay, PostInitializeComponents, EndPlay cleanup, SpawnActor/SpawnActorDeferred/FinishSpawning, CreateDefaultSubobject, NewObject + RegisterComponent, SetupAttachment/AttachToComponent, tick groups, UChildActorComponent, UINTERFACE, actor pooling. Also use when the user mentions 'BeginPlay', 'Tick', 'SpawnActor', 'CreateDefaultSubobject', 'attach a component', 'root component', 'lifecycle', 'PrimaryActorTick', 'FAtt

Use when writing or debugging Unreal Engine animation C++: AnimInstance subclasses, thread-safe update, FAnimInstanceProxy, montage playback and delegates, anim notifies, animation curves, blend spaces, anim state machines, linked anim layers, root motion. Also use when the user mentions 'UAnimInstance', 'NativeUpdateAnimation', 'NativeThreadSafeUpdateAnimation', 'Montage_Play', 'OnMontageEnded', 'UAnimNotify', 'UAnimNotifyState', 'branching point', 'GetCurveValue', 'blend space', 'AnimGraph', '

Use when writing or fixing Unreal Engine gameplay framework classes — GameMode, GameState, PlayerController, PlayerState, Pawn, Character, HUD, GameInstance — and the flows they own: player join, pawn spawning, match state, travel and non-GAS damage. Also use when the user mentions 'AGameModeBase', 'PostLogin', 'OnPostLogin', 'RestartPlayer', 'SpawnDefaultPawnFor', 'ChoosePlayerStart', 'match state', 'PossessedBy', 'seamless travel', 'ServerTravel', 'DrawHUD', 'TakeDamage', 'ApplyRadialDamage' o

Use when driving Niagara VFX from C++: spawning a system, overriding User parameters, binding data interfaces, sending gameplay data through Niagara Data Channels, pooling components or handling OnSystemFinished. Also use when the user mentions 'Niagara', 'particle system', 'VFX', 'UNiagaraComponent', 'UNiagaraFunctionLibrary', 'SpawnSystemAtLocation', 'SpawnSystemAttached', 'SetVariableFloat', 'User. parameter', 'data interface', 'ENCPoolMethod', 'sim cache', 'lightweight emitter', 'muzzle flas

Use when writing or fixing Build.cs, Target.cs, .uproject or .uplugin files, creating a module or plugin, or resolving an Unreal build error. Also use when the user mentions 'unresolved external symbol', 'LNK2019', 'cannot open include file', 'C1083', 'MODULENAME_API', 'PublicDependencyModuleNames', 'IWYU', 'PCHUsage', 'IMPLEMENT_MODULE', 'IMPLEMENT_PRIMARY_GAME_MODULE', 'LoadingPhase', 'circular dependency', 'Missing precompiled manifest', 'EngineAssociation', 'IncludeOrderVersion', 'Live Codin

Use when writing C++ for materials or rendering — dynamic material instances, material parameter collections, render targets, scene capture, post process, decals, Nanite, Lumen, MegaLights, Substrate. Also use when the user mentions 'MID', 'CreateDynamicMaterialInstance', 'SetScalarParameterValue', 'UMaterialInstanceDynamic', 'material parameter collection', 'UTextureRenderTarget2D', 'DrawMaterialToRenderTarget', 'scene capture', 'post process volume', 'FPostProcessSettings', 'bOverride_', 'blen

Use when creating, refreshing or repairing `.agents/ue-project-context.md`, the project document every other UE skill reads first. Also use when the user says 'project context', 'set up context', 'UE context', 'scan my project', 'onboard the agent to my project', 'update project context', 'configure project', 'what engine version is this project on', 'which plugins do we have enabled', or complains that UE advice keeps coming out generic. For Build.cs and Target.cs mechanics, see ue-module-build

Use when extending the Unreal Editor from C++ with detail customizations, editor utility widgets, menus, editor modes, asset definitions or editor subsystems. Also use when the user mentions 'IDetailCustomization', 'IPropertyTypeCustomization', 'CustomizeDetails', 'RegisterCustomClassLayout', 'IDetailLayoutBuilder', 'AddCustomRow', 'IPropertyHandle', 'UToolMenus', 'ExtendMenu', 'FToolMenuEntry', 'UEditorUtilityWidget', 'Blutility', 'UAssetActionUtility', 'UEditorSubsystem', 'UEdMode', 'UAssetDef

Use when writing or fixing Unreal Engine UI in C++ — UMG user widgets, Slate widgets, Common UI screens, or MVVM view models. Also use when the user mentions 'UUserWidget', 'NativeConstruct', 'BindWidget', 'CreateWidget', 'AddToViewport', 'ESlateVisibility', 'OnClicked', 'UListView', 'widget animation', 'SNew', 'SLATE_BEGIN_ARGS', 'SCompoundWidget', 'UCommonActivatableWidget', 'activatable widget stack', 'UCommonButtonBase', 'gamepad focus', 'FUIInputConfig', 'UMVVMViewModelBase', 'FieldNotify',

Expert guide for Unreal Engine 5.x C++ development, covering UObject hygiene, performance patterns, and best practices.

Write Unreal Engine 5 C++ gameplay code: the UCLASS/UPROPERTY/UFUNCTION reflection macros, the Gameplay Framework (GameMode, Pawn, Character, PlayerController, Actor components), and the module Build.cs. Use when writing or debugging UE C++, deriving from AActor/ACharacter/ AGameModeBase, exposing properties to the editor or Blueprints, or when the user mentions Unreal C++, UCLASS, GENERATED_BODY, GameMode, ACharacter, or .Build.cs.