Tool Reference
Tool Reference documentation.
UE-MCP exposes 21 category tools covering 569+ actions, plus a flow tool for running multi-step YAML workflows. Every category tool takes an action parameter that selects the operation, plus action-specific parameters.
First call in any session
Start with project(action="get_status") to check the connection, then level(action="get_outliner") or asset(action="list") to explore.
How to read this page
Each row lists a single action and its key parameters. Optional params are marked with ?. For full schemas (types, descriptions, defaults), every action also surfaces its description through the MCP schema - your AI client can introspect them at runtime.
project
Project status, config INI files, and C++ source inspection.
| Action | Description |
|---|---|
get_status | Check server mode and editor connection |
set_project | Switch project. Params: projectPath |
get_info | Read .uproject file details |
read_config | Read INI config. Params: configName (e.g. 'Engine', 'Game') |
search_config | Search INI files. Params: query |
list_config_tags | Extract gameplay tags from config |
read_cpp_header | Parse a .h file. Params: headerPath |
read_module | Read module source. Params: moduleName |
list_modules | List C++ modules |
search_cpp | Search .h/.cpp files. Params: query, directory? |
read_engine_header | Parse a .h file from the engine source tree. Params: headerPath (relative to Engine/Source, or absolute) |
find_engine_symbol | Grep engine headers for a symbol. Params: symbol, maxResults? |
list_engine_modules | List modules in Engine/Source/Runtime |
search_engine_cpp | Search engine .h/.cpp/.inl files across Runtime/Editor/Developer/Plugins. Params: `query, tree? (Runtime\ |
set_config | Write to INI. Params: configName, section, key, value |
build | Build C++ project. Params: configuration?, platform?, clean? |
generate_project_files | Generate IDE project files (Visual Studio, Xcode, etc.) |
create_cpp_class | Create a new native UCLASS in a project module. Uses the same engine template path as File → New C++ Class. Writes .h + .cpp; returns both paths plus needsEditorRestart (true unless Live Coding successfully hot-reloaded). Params: `className (no prefix), parentClass? (default UObject; accepts short names like 'Actor' or /Script/[Module].[Class] paths), moduleName? (default: first project module, use list_project_modules to pick), classDomain? ('public'\ |
list_project_modules | List native modules in the current project (name, host type, source path). Feed moduleName from here into create_cpp_class |
live_coding_compile | Trigger a Live Coding compile (Windows only). Hot-patches method bodies of existing UCLASSes without editor restart - the fast inner loop for UFUNCTION implementations. Does NOT reliably register brand-new UCLASSes; use build_project + editor restart for those. Params: wait? (default false - fire and return 'in_progress') |
live_coding_status | Report Live Coding availability/state (available, started, enabledForSession, compiling). Helps choose between live_coding_compile and build_project |
write_cpp_file | Write a .h / .cpp / .inl file under the project's Source/ tree. Used to append UPROPERTYs/UFUNCTIONs or method bodies after create_cpp_class. Writes are scoped to Source/ for safety. Params: path (relative to Source/ or absolute within Source/), content (full file contents) |
read_cpp_source | Read a .cpp file from the project Source/ tree. Companion to read_cpp_header for round-trip edits. Params: sourcePath (relative to Source/ or absolute) |
write_source_file | Write a .h/.cpp/.inl into a named module's Public/Private folder (resolves the module dir for you, including plugin modules under Plugins/*/Source/ that write_cpp_file refuses). After a new file, build_project + restart; after a body edit, live_coding_compile. Params: `module (module name, default the project's primary module), visibility (Public\ |
read_source_file | Read a .h/.cpp/.inl from a named module's folder (companion to write_source_file; resolves plugin modules too). With no visibility it tries Public then Private then the module root. Params: module, visibility?, fileName |
add_module_dependency | Add a module to a target module's Build.cs dependency array. Params: `moduleName (the Build.cs to edit - must exist in the project), dependency (module name to add, e.g. 'UMG'), access? ('public'\ |
add_cpp_member | Append a UPROPERTY/UFUNCTION declaration to an existing UCLASS header inside the access specifier you choose. Idempotent: if a declaration containing the same memberName is already present, returns existed:true. Params: `headerPath (relative to Source/ or absolute), declaration (full multi-line UPROPERTY(...) / UFUNCTION(...) block plus its single-line member or function signature), memberName (the identifier the declaration introduces - used for idempotency), access? ('public'\ |
asset
Asset management: list, search, read, CRUD, import meshes/textures, datatables.
| Action | Description |
|---|---|
list | List assets via the AssetRegistry (sees /Game and every mounted plugin root). Params: directory? (default /Game), classFilter?, recursive? (default true), maxResults? (default 2000) |
search | Search by name/class/path. Params: query, directory?, maxResults?, searchAll? |
read | Read asset via reflection. Params: assetPath |
read_properties | Read asset properties with values. propertyName accepts dotted/indexed paths into nested structs, array elements, and instanced subobjects (e.g. Config.Traits[1].Params.Field); landing on an array of subobjects also lists each element's index+class (#527). Params: assetPath, propertyName?, includeValues? |
duplicate | Duplicate asset. Params: sourcePath, destinationPath |
rename | Rename asset. Params: assetPath, newName (or sourcePath, destinationPath), force? |
bulk_rename | Batched rename using IAssetTools::RenameAssets - single transaction with one redirector-fixup pass (matches Content Browser drag). Use this over looped rename for scene-referenced assets. World assets are rejected (status=rejected_world); use rename_asset which handles WP externals atomically (#409). Params: renames[] where each entry is (sourcePath, destinationPath) OR (assetPath, newName) |
move | Move asset. Params: sourcePath, destinationPath |
delete | Delete asset. On failure returns reason (open_in_editor / has_referencers / unknown) plus referencer list. Pass force=true to auto-close any open asset editors before deleting (#278). Params: assetPath, force? |
delete_batch | Batch-delete assets. Per-path status (deleted/absent/failed) plus reason+referencers on failed entries (#278). Params: assetPaths[], force? |
create_data_asset | Create UDataAsset instance of custom class. Params: name, className (/Script/Module.ClassName or loaded name), packagePath?, properties? (key/value map) |
save | Save asset(s). Params: assetPath? |
save_all_dirty | Flush every dirty package to disk in one call. End-of-workflow shortcut after bulk import/edit. Params: saveMapPackages? (default true), saveContentPackages? (default true) |
set_mesh_material | Assign material to static mesh slot. Params: assetPath, materialPath, slotIndex? |
recenter_pivot | Move static mesh pivot to geometry center. Params: assetPath OR assetPaths |
import_static_mesh | Import from FBX/OBJ. Params: filePath, name?, packagePath?, combineMeshes?, importMaterials?, importTextures?, generateLightmapUVs? |
import_skeletal_mesh | Import skeletal mesh from FBX. Params: filePath, name?, packagePath?, skeletonPath?, importMaterials?, importTextures? |
import_animation | Import anim from FBX. Params: filePath, name?, packagePath?, skeletonPath |
import_texture | Import image. Params: filePath, name?, packagePath? |
import_texture_batch | Import many textures in one call - the loop stays inside the editor (no per-file bridge round-trip), so this finishes far faster than N import_texture calls. Per-item result records mirror import_texture. Params: items[]: [(filePath, packagePath?, name?, replaceExisting?)], packagePath? (default for items that don't set it), save? (default true), automated? (default true) |
reimport | Reimport asset from source file. Params: assetPath, filePath? |
read_datatable | Read DataTable rows. Params: assetPath, rowFilter? |
create_datatable | Create DataTable. Params: name, packagePath?, rowStruct |
reimport_datatable | Reimport DataTable from JSON. Params: assetPath, jsonPath?, jsonString? |
set_datatable_row | Append or overwrite a single DataTable row. Params: assetPath, rowName, row (object with row-struct fields - partial updates merge with the existing row) |
add_datatable_row | Alias for set_datatable_row (#437) |
update_datatable_row | Alias for set_datatable_row; partial update merges with existing row (#437) |
remove_datatable_row | Remove a single DataTable row. Idempotent (alreadyDeleted=true if missing). Params: assetPath, rowName (#437) |
get_datatable_row | Read one DataTable row's fields without dumping the whole table. Params: assetPath, rowName (#535) |
set_datatable_cell | Write a single field on a single existing row (merges, leaves other cells untouched). Errors if the row doesn't exist. Params: assetPath, rowName, fieldName, value (#535) |
rename_datatable_row | Rename a row key, preserving its values. Params: assetPath, oldName, newName (#535) |
fill_datatable_from_json | Bulk-upsert rows from a {rowName: {field: value}} object without touching unrelated rows (non-destructive, unlike reimport_datatable). Params: assetPath, rows (object) or jsonString (#535) |
list_textures | List textures. Params: directory?, recursive? |
get_texture_info | Get texture details. Params: assetPath |
set_texture_settings | Set texture settings. Params: assetPath, settings (object with compressionSettings?, lodGroup?, sRGB?, neverStream?) |
add_input_mapping | Append an Enhanced Input key mapping to an InputMappingContext (InputAction + key by name string e.g. 'Mouse2D','LeftMouseButton'). Idempotent on (action,key). For modifiers/triggers use gameplay(set_mapping_modifiers). Same as gameplay(add_imc_mapping) (#525). Params: mappingContext (IMC path), inputAction (IA path), key |
remove_input_mapping | Remove an IMC key mapping. Same as gameplay(remove_imc_mapping) (#525). Params: `mappingContext (IMC path), mappingIndex? \ |
list_input_mappings | List an IMC's key->action bindings with triggers/modifiers. Same as gameplay(read_imc) (#525). Params: mappingContext (IMC path) |
add_socket | Add socket to StaticMesh or SkeletalMesh. Idempotent on socket name; pass onConflict='update' to overwrite an existing socket's transform with the supplied relativeLocation/relativeRotation/relativeScale (#412). Params: assetPath, socketName, boneName? (SkeletalMesh only, default 'root'), relativeLocation?, relativeRotation?, relativeScale?, onConflict? (skip\\|update\\|error, default skip) |
remove_socket | Remove socket by name. Params: assetPath, socketName |
list_sockets | List sockets on a mesh (StaticMesh or SkeletalMesh). Params: assetPath |
set_socket_transform | Update an existing socket's relative transform on StaticMesh or SkeletalMesh. Pass any subset of relativeLocation/relativeRotation/relativeScale; omitted fields stay at their current values. Errors if the socket does not exist (use add_socket to create). Common after FBX import when SOCKET_* empties land with scale=(100,100,100) (#412). Params: assetPath, socketName, relativeLocation?, relativeRotation?, relativeScale? |
set_property | Set a UPROPERTY on any loaded asset (Material, DataAsset, DataTable, SubsurfaceProfile, etc.) using a dotted path. Walks nested structs, array elements by index, and instanced subobjects internally - no more read-modify-write copies (e.g. settings.mean_free_path_distance on a UMaterial, or Config.Traits[1].Params.Field on a config asset #527). Value goes through MCPJsonProperty::SetJsonOnProperty so JSON null clears object refs, structs accept {x,y,z}, arrays/maps round-trip. Params: assetPath, propertyName (dotted path), value (#420) |
set_texture_settings_by_type | Apply the canonical (compressionSettings, sRGB, LOD group) combo to every texture in each group: normal -> Normalmap, grayscale -> Grayscale, baseColor -> Default sRGB, hdr -> HDR. Params: groups (object: (normal?:[paths], grayscale?:[paths], baseColor?:[paths], hdr?:[paths])) (#421) |
create_interchange_pipeline | One-call factory for a UInterchangeGenericAssetsPipeline asset with the 15-property mesh-import boilerplate already applied (RecomputeNormals=false, MikkTSpace=true, HighPrecisionTangents=true, BuildNanite=false, CreatePhysicsAsset=false, etc.). Params: `assetPath OR (name + packagePath?), meshType? (skeletal default \ |
reload_package | Force reload an asset package from disk. Params: assetPath |
health_check | Diagnose stuck-unloadable asset. Returns onDisk/inRegistry/isLoaded/canLoad/isStuck flags so an agent can detect the half-shutdown state where load returns null but the file exists (#279). Params: assetPath |
force_reload | Aggressive reload that resets package loaders + GCs + LoadObject. Recovers from the half-shutdown state without an editor restart (#279). Closes any open editors first. Params: assetPath |
export | Export asset to disk file (Texture2D → PNG, StaticMesh → FBX, etc.). Params: assetPath, outputPath |
search_fts | Ranked asset search (token-scored over name/class/path). Params: query, maxResults?, classFilter? |
reindex_fts | Rebuild the SQLite FTS5 asset index. Params: directory? |
get_referencers | Reverse dependency lookup. Params: packages[] OR packagePath (#150) |
set_sk_material_slots | Set materials on a USkeletalMesh by slot name or slotIndex (bypasses the blueprint override-materials path that UE's ICH silently reverts). Params: `assetPath, slots[(slotName?\ |
diagnose_registry | Scan a content path and compare disk vs AssetRegistry (including in-memory pending-kill entries). Returns onDiskCount, inMemoryIncludedCount, ghostCount and paths. Params: path, recursive? (default true), reconcile? (forceRescan=true) |
get_mesh_bounds | Get StaticMesh OR SkeletalMesh bounding box. Params: assetPath |
get_mesh_info | One-call mesh QA: bounds + material slots + skeleton + LOD/vertex counts. Works for both UStaticMesh and USkeletalMesh. Params: assetPath |
read_import_sources | Read AssetImportData source filenames on an imported asset (StaticMesh, SkeletalMesh, Texture, Animation, etc.). Returns sources[] of {relativeFilename, absolutePath, timestamp, fileHash, displayLabelName}. Params: assetPath (#270) |
get_mesh_collision | Inspect StaticMesh collision setup. Params: assetPath |
move_folder | Move/rename entire content folder with redirector fixup in one transaction. Params: sourcePath, destinationPath (#192) |
create_folder | Create empty content browser folder(s). Params: path OR paths[] (e.g. /Game/Foo, /Game/Bar/Baz) |
delete_folder | Delete content browser folder(s) - counterpart to delete_asset, which leaves the parent directory entry behind as an orphan. Empty folders only by default; pass force=true to also delete any assets still inside (Content Browser 'Delete folder' equivalent). Per-path status (deleted/absent/failed) with reason (invalid_path/protected_path/not_empty/delete_failed) and a sample of contained assets on not_empty entries. Params: path OR paths[], force? |
set_mesh_nav | Set StaticMesh nav contribution. Params: assetPath, bHasNavigationData?, clearNavCollision? (#167) |
blueprint
Blueprint reading, authoring, and compilation. Covers variables, functions, graphs, nodes, components, interfaces, and event dispatchers.
| Action | Description |
|---|---|
read | Read BP structure incl. SCS components AND inherited native components from the CDO (CharacterMesh0, CharMoveComp, etc.). Params: assetPath, includeComponentProperties? (dump UPROPERTY name/type/value per component template; off by default) (#353/#370) |
list_variables | List variables. Params: assetPath |
list_functions | List functions/graphs. Params: assetPath |
read_graph | Read graph nodes. Supports pagination and file dumps. Params: assetPath, graphName, offset?, limit?, includePins?, includeDefaults?, includeComments?, dumpToFile?, outputPath? |
read_graph_summary | Lightweight graph summary (nodes+edges only, ~10KB). Params: assetPath, graphName? |
get_execution_flow | Trace exec pins from an entry point. Params: assetPath, graphName?, entryPoint? |
get_dependencies | Forward (classes/functions/assets) or reverse (referencers) deps. Params: assetPath, reverse? |
create | Create Blueprint. Params: assetPath, parentClass? |
add_variable | Add variable. Params: assetPath, name, varType |
set_variable_properties | Edit variable properties. Params: assetPath, name, instanceEditable?, blueprintReadOnly?, category?, tooltip?, replicationType?, exposeOnSpawn? |
create_function | Create function. Params: assetPath, functionName |
delete_function | Delete function. Params: assetPath, functionName |
rename_function | Rename function. Params: assetPath, oldName, newName |
add_node | Add graph node. For a CallFunction node bound to a custom C++ UFUNCTION, pass nodeParams {functionName, className (or targetClass) = /Script/Module.Class}; the function also resolves against the BP's own component classes and an unambiguous loaded BlueprintCallable function, producing a bound node with pins instead of a stub (#546). Params: assetPath, graphName?, nodeClass, nodeParams? |
delete_node | Delete node. Params: assetPath, graphName, nodeName |
set_node_property | Set node pin default or struct property. Params: assetPath, graphName, nodeName, propertyName, value |
connect_pins | Wire nodes. Params: sourceNode, sourcePin, targetNode, targetPin, assetPath, graphName? |
add_component | Add BP component. componentClass accepts short names (e.g. 'ChildActorComponent') or full paths. For a ChildActorComponent, pass childActorClass to set its ChildActorClass in the same call (a Blueprint path with or without _C, or a C++ class) (#526). Params: assetPath, componentClass, componentName?, parentComponent? (SCS parent for hierarchy - #115), childActorClass? |
remove_component | Remove SCS component. Params: assetPath, componentName |
set_component_property | Set property on SCS or inherited component. Inherited components go through the child BP's InheritableComponentHandler override template so the parent stays untouched. Pass value=null to clear a TObjectPtr/SoftObject/WeakObject/UClass/Interface reference (e.g. clear AnimClass on CharacterMesh0) (#420). Params: assetPath, componentName, propertyName, value |
set_component_override_materials | Write OverrideMaterials on a mesh-component template (StaticMeshComponent / SkeletalMeshComponent / any UMeshComponent). Pass materialPaths as a string[] of material asset paths (empty array clears). Avoids any TArray<UObject*> coercion on the generic set_component_property path (#442). Params: assetPath, componentName, materialPaths |
add_timeline_track | Add a track to a Blueprint timeline. Creates the UTimelineTemplate if missing, builds the matching curve asset (float/vector/color/event), applies keyframes, bumps TimelineLength to cover the last key, then recompiles so K2Node_Timeline regenerates its output pins. Params: `assetPath, timelineName, trackName, trackType ('float'\ |
set_capsule_size | Call UCapsuleComponent::SetCapsuleSize on a CapsuleComponent template (CharacterMovement-friendly path; raw property writes leave the visualizer stale). Pass either or both of halfHeight/radius. Returns the new + previous values. Params: assetPath, componentName, halfHeight?, radius? (#419) |
get_component_property | Read a single property value from an SCS or inherited component template. Returns the ICH override value for child BPs if one exists. Params: assetPath, componentName, propertyName |
set_class_default | Set UPROPERTY on Blueprint CDO. Pass value=null to clear an object/class/interface reference (#420). Params: assetPath, propertyName, value |
delete_variable | Delete a member variable. Params: assetPath, name |
add_function_parameter | Add input or output parameter to a function. Params: assetPath, functionName, parameterName, parameterType?, isOutput? |
set_variable_default | Set default value on a BP variable. Params: assetPath, name, value |
compile | Compile Blueprint. Params: assetPath |
list_node_types | List node types. Params: category?, includeFunctions? |
search_node_types | Search nodes. Params: query |
create_interface | Create BP Interface. Params: assetPath |
add_interface | Implement interface. Params: blueprintPath, interfacePath |
list_graphs | List all graphs in a blueprint. Params: assetPath |
add_event_dispatcher | Add event dispatcher (multicast delegate variable + signature graph + UFunction). Without parameters, broadcasters fire void(). With parameters, the signature graph gets typed user pins so K2Node_CallDelegate compiles cleanly (#276). Params: blueprintPath, name, parameters?: [(name, type)] where type is bool/int/float/string/name/text/vector/rotator/transform/object:/Script/Module.Class/struct:/Script/Module.Struct |
duplicate | Duplicate blueprint asset. Params: sourcePath, destinationPath |
add_local_variable | Add function-scope local variable. Params: assetPath, functionName, name, varType? |
list_local_variables | List local variables in a function. Params: assetPath, functionName |
validate | Validate blueprint without saving (compile + collect diagnostics). Params: assetPath |
read_component_properties | Dump ALL UPROPERTYs on a BP component template incl. array contents (#105). Params: assetPath, componentName |
read_node_property | Read a node pin default OR a reflected node property for verification (#102). Params: assetPath, graphName?, nodeName, propertyName |
reparent_component | Reparent an SCS component under a new parent (#115). Params: assetPath, componentName, newParent |
reparent | Change a Blueprint's ParentClass and recompile (#138). Params: assetPath, parentClass (short name or full path) |
set_actor_tick_settings | Set actor CDO tick settings (#116). Params: assetPath, bCanEverTick?, bStartWithTickEnabled?, TickInterval? |
export_nodes_t3d | Export graph nodes as T3D text (Ctrl+C equivalent) for bulk round-trip (#130). Params: assetPath, graphName?, nodeIds? (omit = whole graph) |
import_nodes_t3d | Paste a T3D node blob into a graph (Ctrl+V equivalent) for bulk authoring (#130). Params: assetPath, graphName?, t3d, posX?, posY? |
set_cdo_property | Set UPROPERTY on any C++ class CDO (not just Blueprints). Params: className, propertyName, value (#182/#183) |
get_cdo_properties | Read UPROPERTY values from any C++ class CDO. Params: className, propertyNames? (#183) |
run_construction_script | Spawn temp actor, run construction script, return generated components and transforms. Params: assetPath, location? (#195) |
compile_all | Batch compile + save Blueprints. Params: assetPaths[], save? (default true) |
cleanup_graph | Remove orphan/corrupted nodes (no class, blank title+no pins, missing target UFunction). Params: assetPath, graphName? (default: every graph) (#285) |
connect_pins_batch | Apply many pin connections in one call (single compile + save). Params: assetPath, graphName?, connections[]: [(sourceNode, sourcePin, targetNode, targetPin)] (#267) |
set_node_position | Move a graph node to (posX, posY). Params: assetPath, graphName?, nodeId, posX, posY (#277) |
auto_layout | Topological layered layout for a graph. Eliminates the (0,0) stack from programmatic add_node. Params: assetPath, graphName?, columnGap? (default 360), rowGap? (default 200) (#277) |
level
Level actors, selection, components, level management, volumes, lights, and splines.
| Action | Description |
|---|---|
get_outliner | List actors. Params: `classFilter?, nameFilter?, world? (editor\ |
place_actor | Spawn actor. Params: actorClass, label?, location?, rotation?, scale?, staticMesh?, material? |
delete_actor | Remove actor. Params: actorLabel |
get_actor_details | Inspect actor. Params: `actorLabel OR actorPath, includeProperties?, propertyName?, world? (editor\ |
move_actor | Transform actor. Params: actorLabel, location?, rotation?, scale? |
select | Select actors. Params: actorLabels[] |
get_selected | Get selection |
add_component | Add component to actor. Params: actorLabel, componentClass, componentName? |
remove_component | Remove instance component from a level actor by name. Idempotent: returns alreadyDeleted=true if no matching component exists. Params: actorLabel, componentName (#426) |
set_component_property | Set component prop. Pass value=null to clear a TObjectPtr/SoftObject/WeakObject/UClass/Interface reference (#420). Resolves inherited/SCS components on placed Blueprint instances case-insensitively, and refreshes the scene transform after RelativeLocation/RelativeRotation/RelativeScale3D writes (#539). Params: actorLabel, componentName, propertyName, value |
get_component_details | Read a placed actor's component transforms. With componentName returns that component's relative+world location/rotation/scale, class, and attach parent; without it lists every component with its transform. Resolves SCS components on Blueprint instances (#539). Params: actorLabel, componentName? |
get_current | Get current level name and path |
load | Load level. Params: levelPath |
save | Save current level |
list | List levels. Params: directory?, recursive? |
create | Create new level. Params: levelPath?, templateLevel? |
spawn_volume | Place volume. Params: volumeType, location?, extent?, label? |
list_volumes | List volumes. Params: volumeType? |
set_volume_properties | Edit volume. Params: actorLabel, properties |
spawn_light | Place light. Params: `lightType (point\ |
set_light_properties | Edit light. Params: `actorLabel, intensity?, color?, rotation? (DirectionalLight sun angle), mobility? (static\ |
set_fog_properties | Edit ExponentialHeightFog. Params: actorLabel?, fogDensity?, fogHeightFalloff?, startDistance?, fogInscatteringColor? |
get_actors_by_class | List actors by class name. Params: `className, world? (editor\ |
count_actors_by_class | Histogram of actor classes in the level (sorted desc). Params: `world? (editor\ |
get_runtime_virtual_texture_summary | List RuntimeVirtualTextureVolume actors + their bound VirtualTexture assets (#150) |
set_water_body_property | Set a property on an actor's WaterBodyComponent (ShapeDilation, WaterLevel, etc.). Params: actorLabel, propertyName, value |
build_lighting | Build lights. Params: quality? |
get_spline_info | Read spline. Params: actorLabel |
set_spline_points | Set spline points. Params: actorLabel, points[], closedLoop? |
set_actor_material | Set material on actor. Params: actorLabel, materialPath, slotIndex? |
get_world_settings | Read world settings (GameMode, KillZ, gravity, etc.) |
set_world_settings | Set world settings. Params: defaultGameMode?, killZ?, globalGravityZ?, enableWorldBoundsChecks? |
get_actor_bounds | Get actor AABB. Params: actorLabel |
get_component_tree | Deep component-tree dump for an actor. Returns per-component: name, class, attachParent, attachSocket, mobility, visibility, relative+world transforms, tags. For PrimitiveComponents adds collisionProfile/collisionEnabled/bounds/castShadow. For StaticMeshComponent adds staticMesh + materials[]. For SkeletalMeshComponent adds skeletalMesh + skeleton + materials[]. Params: `actorLabel \ |
get_relative_transform | Compute target's transform in reference's local space (location/rotation/scale). Common dungeon/calibration workflow. Params: target (actor label), reference (actor label), world? (#386/#387) |
resolve_actor | Resolve internal/runtime actor name to editor label. Params: internalName (e.g. StaticMeshActor_141) |
set_actor_property | Set per-instance UPROPERTY on a level actor. Params: `actorLabel ('WorldSettings' targets the world settings actor), propertyName (dotted paths like 'Foo.Bar' supported), value (string/number/bool/object/array; a label string resolves to an AActor* ref, and a JSON array of labels populates a TArray of actor refs #538), force? (bypass EditDefaultsOnly), world? (editor\ |
read_actor_motion | Snapshot motion telemetry for one or many actors: location, rotation, velocity, scale, angularVelocity (when simulating physics), grounded + distanceToGround (downward 200u trace). Defaults to the PIE world with editor fallback. Loop at your sample interval for long telemetry probes. Params: `actorLabel? OR actorLabels (string[]), world? ('pie'\ |
add_hismc_instances | Bulk-add transforms to a HISMC / ISMC component on an actor (Python add_instance crashes on UE 5.7; this is the C++ path). Params: actorLabel, componentName? (default: first ISMC/HISMC found), transforms ([(location: (x,y,z), rotation?: (pitch,yaw,roll), scale?: (x,y,z))]), worldSpace? (default true) (#434) |
delete_actors | Bulk-delete actors. Params: at least one of labelPrefix, className, tag; dryRun? to preview |
add_actor_tag | Append a tag to an actor's Tags array. Params: actorLabel, tag (#219) |
remove_actor_tag | Remove a tag from an actor's Tags array. Params: actorLabel, tag (#219) |
set_actor_tags | Replace an actor's Tags array. Params: actorLabel, tags[] (#219) |
list_actor_tags | List an actor's Tags. Params: actorLabel (#219) |
attach_actor | Attach actor as child. Params: `childLabel, parentLabel, attachRule? (KeepWorld\ |
detach_actor | Detach actor from parent. Params: childLabel (#205) |
set_actor_mobility | Set actor root component Mobility. Params: `actorLabel, mobility (static\ |
get_current_edit_level | Read the active edit-target sub-level (#204) |
set_current_edit_level | Set the active edit-target sub-level so subsequent spawns land in it. Params: levelName (e.g. SubLevel_A) (#204) |
list_streaming_sublevels | List streaming sub-levels with transform + initially-loaded/visible flags (#206) |
add_streaming_sublevel | Add a streaming sub-level. Params: `levelPath, streamingClass? (LevelStreamingDynamic\ |
remove_streaming_sublevel | Remove a streaming sub-level. Params: `levelName \ |
set_streaming_sublevel_properties | Update sub-level transform/visibility flags. Params: `levelName \ |
spawn_grid | Batch-spawn StaticMeshActors on a grid. Params: staticMesh, min, max (Vec3 bounds), countX?, countY?, countZ?, jitter?, labelPrefix? (#203) |
batch_translate | Translate a set of actors by an offset. Params: offset (Vec3), actorLabels[] OR tag (#203) |
place_actors_batch | Bulk-spawn StaticMeshActors with per-instance mesh + transform. Params: actors[]: [(staticMesh, location?, rotation?, scale?, label?)] |
line_trace | Line trace in the editor world. Returns hit + actorLabel/actorClass/componentName/componentClass/location/impactPoint/normal/distance/faceIndex/boneName/physicalMaterial. Params: start (Vec3), end? (Vec3) OR direction? (Vec3) + distance? (default 200000), ignoreActors? (array of labels) (#420) |
snap_actor_to_floor | Snap an actor's bounds-bottom to the first downward line-trace hit. Equivalent of the End-key shortcut, works on arbitrary geometry (not just Landscape). Params: actorLabel, floorOffset? (added to impact Z, default 0), maxDistance? (default 100000) (#419) |
material
Materials: create, read, parameters, shading, textures, and graph authoring (expression nodes, connections).
| Action | Description |
|---|---|
read | Read material structure. Params: assetPath |
list_parameters | List overridable parameters. Params: assetPath |
set_parameter | Set parameter on MaterialInstance. Params: assetPath, parameterName, parameterType, value |
set_expression_value | Set value on expression node. Params: materialPath, expressionIndex, value |
disconnect_property | Disconnect a material property input. Params: materialPath, property |
create_instance | Create material instance. Params: parentPath, name?, packagePath? |
create | Create material. Params: name, packagePath? |
create_function | Create a MaterialFunction asset. Params: name, packagePath? (default /Game/Materials/Functions), description? (#463) |
add_function_expression | Add an expression node to a MaterialFunction graph. Params: `functionPath, expressionType (e.g. Constant3Vector, FunctionInput, FunctionOutput, If), positionX?, positionY?, inputName? (for FunctionInput), inputType? (Scalar\ |
connect_function_expressions | Wire two expressions inside a MaterialFunction. Params: functionPath, sourceExpression (name or index), sourceOutput?, targetExpression (name or index), targetInput? (#463) |
list_function_expressions | List expression nodes inside a MaterialFunction. Params: functionPath (#463) |
create_simple | Single-call simple material. Params: name, packagePath?, baseColor? ((r,g,b)), metallic?, specular?, roughness?, emissive?, usages?[] (e.g. InstancedStaticMeshes, Nanite, NiagaraSprites) |
set_usage | Set EMaterialUsage flag(s) on a material. Params: assetPath, usage OR usages[], enabled? (default true) |
set_shading_model | Set shading model. Params: assetPath, shadingModel |
set_blend_mode | Set blend mode. Params: assetPath, blendMode |
set_domain | Set material domain. Params: `assetPath, materialDomain (Surface \ |
set_base_color | Set base color. Params: assetPath, color |
connect_texture | Connect texture to property. Params: materialPath, texturePath, property |
add_expression | Add expression node. Params: materialPath, expressionType, name?, parameterName?, group?, sortPriority?, defaultValue? (scalar number or (r,g,b,a) for vector params), value? (number for Constant, (r,g,b) for Constant3Vector, (x,y) for Constant2Vector), channels? ((r,g,b,a) bools for ComponentMask), positionX?, positionY? (#318) |
connect_expressions | Wire two expressions. Params: materialPath, sourceExpression, sourceOutput?, targetExpression, targetInput? |
connect_to_property | Wire expression to material output. Params: materialPath, expressionName, outputName?, property |
list_expressions | List expression nodes. Params: materialPath |
delete_expression | Remove expression. Params: materialPath, expressionName |
list_expression_types | List available expression types |
recompile | Recompile material. Pass recompileChildren=true to cascade to every MaterialInstanceConstant whose parent chain reaches this material (#421). Params: materialPath, recompileChildren? |
duplicate | Duplicate material asset. Params: sourcePath, destinationPath |
validate | Validate material graph - find orphans, broken refs. Params: assetPath |
get_shader_stats | Shader compile stats, sampler+param counts. Params: assetPath |
export_graph | Export material graph as JSON. Params: assetPath |
import_graph | Rebuild graph from JSON. Params: assetPath, nodes, propertyConnections? |
build_graph | Build graph from spec. Params: assetPath, nodes, propertyConnections? |
render_preview | Render preview PNG. Params: assetPath, outputPath, width?, height? |
begin_transaction | Begin undo transaction. Params: label? |
end_transaction | End undo transaction |
animation
Animation assets, skeletons, montages, blendspaces, anim blueprints, physics assets.
| Action | Description |
|---|---|
read_anim_blueprint | Read AnimBP structure. Params: assetPath |
read_montage | Read montage. Params: assetPath |
read_sequence | Read anim sequence. Params: assetPath |
scan_animation_tracks | Scan AnimSequence bone-track counts. Params: directory?, recursive?, assetPaths?, skeletonPath?, targetTrackCount?, includeTrackNames? |
read_blendspace | Read blendspace. Params: assetPath |
add_blend_sample | Append a sample to a BlendSpace. Params: assetPath, animation (AnimSequence path), position (x,y) (or flat x,y) (#248) |
set_blend_sample | Move an existing BlendSpace sample or swap its animation. Params: assetPath, sampleIndex, position? (x,y) (or flat x,y), animation? (#272) |
list | List anim assets. Params: directory?, recursive? |
create_montage | Create montage. Params: animSequencePath, name?, packagePath? |
create_anim_blueprint | Create AnimBP. Params: skeletonPath, name?, packagePath?, parentClass? |
create_blendspace | Create blendspace (2D). Params: skeletonPath, name?, packagePath?, axisHorizontal?, axisVertical? |
create_blendspace_1d | Create BlendSpace1D. Params: skeletonPath, name?, packagePath?, axisName? (default Speed), axisMin?, axisMax?, gridNum? (#459) |
populate_blendspace | One-call axis params + samples authoring for BlendSpace 1D/2D. Params: assetPath, axis? ((name?, min?, max?, gridNum?)) for axis 0, blendspaceAxes? (per-axis array), axisHorizontal?/axisVertical? + horizontalMin/horizontalMax/verticalMin/verticalMax/gridNumHorizontal/gridNumVertical (back-compat), samples ([(animationPath, x, y?)]), clearExisting? (default true) (#459) |
add_notify | Add notify. For PlayMontageNotify the notifyName is also written onto the spawned notify object so OnPlayMontageNotifyBegin broadcasts it (not 'None'), and montage branching-point markers refresh (#528). Params: assetPath, notifyName, triggerTime, notifyClass? |
remove_notify | Remove notify(s) by name and/or class. Pass at least one of notifyName/notifyClass; both filters AND. Idempotent: alreadyDeleted=true if no match. Params: assetPath, notifyName?, notifyClass? (#471) |
get_skeleton_info | Read skeleton. Params: assetPath |
list_sockets | List sockets. Params: assetPath |
list_skeletal_meshes | List skeletal meshes. Params: directory?, recursive? |
get_physics_asset | Read physics asset. Params: assetPath |
create_sequence | Create blank AnimSequence. Params: name, skeletonPath, packagePath?, numFrames?, frameRate? |
set_bone_keyframes | Set bone transform keyframes. Params: assetPath, boneName, keyframes |
bake_keyframes_batch | Bake per-bone keyframe arrays for many bones into an AnimSequence in one call. Auto-creates each bone track first (set_bone_keyframes silently leaves a T-pose if the track is missing), wraps the batch in one transaction, and raises if any bone fails instead of reporting hollow success (#540). Params: assetPath, tracks ([(bone, keyframes:[(location,rotation(x,y,z,w),scale?)])]), save? (default true) |
get_bone_transforms | Read reference pose transforms. Params: skeletonPath, boneNames?, space? ('local' default, or 'component' for composed parent-chain transforms - retarget-chain / anatomical-scale work) (#245) |
set_montage_sequence | Replace animation sequence in a montage. Params: assetPath, animSequencePath, slotIndex? |
set_montage_properties | Set montage properties. Params: assetPath, sequenceLength?, rateScale?, blendIn?, blendOut? |
create_state_machine | Create state machine in AnimBP. Params: assetPath, name?, graphName? |
add_state | Add state to a state machine. Params: assetPath, stateMachineName, stateName |
add_transition | Add directed transition between states. Params: assetPath, stateMachineName, fromState, toState |
set_state_animation | Assign anim asset to state. Params: assetPath, stateMachineName, stateName, animAssetPath |
set_transition_blend | Set blend type/duration on transition. Params: assetPath, stateMachineName, fromState, toState, blendDuration?, blendLogic? |
read_state_machine | Read state machine topology. Params: assetPath, stateMachineName |
read_anim_graph | Read AnimBP AnimGraph nodes with properties & pins. Params: assetPath, graphName? |
add_curve | Add float curve to AnimSequence. Params: assetPath, curveName, curveType? |
set_montage_slot | Set slot name on a montage track. Params: assetPath, slotName, trackIndex? |
add_montage_section | Add composite section to montage. Params: assetPath, sectionName, startTime?, linkedSection? |
create_ik_rig | Create IKRigDefinition asset, optionally with retargetRoot + chains[]. Params: name, skeletalMeshPath, packagePath?, retargetRoot?, chains?: [(name, startBone, endBone, goal?)] |
read_ik_rig | Read IK Rig chains, solvers, skeleton. Params: assetPath |
list_control_rig_variables | List ControlRig variables and hierarchy. Params: assetPath |
set_root_motion | Set root motion settings on AnimSequence. Params: assetPath, enableRootMotion?, forceRootLock?, useNormalizedRootMotionScale?, rootMotionRootLock? |
add_virtual_bone | Add virtual bone. Params: skeletonPath, sourceBone, targetBone |
remove_virtual_bone | Remove virtual bone. Params: skeletonPath, virtualBoneName |
create_composite | Create AnimComposite. Params: name, skeletonPath, packagePath? |
list_modifiers | List applied animation modifiers. Params: assetPath |
create_ik_retargeter | Create IKRetargeter asset and (default) initialize the UE 5.7 ops stack: assigns sourceRig+targetRig to all ops, runs AutoMapChains. Returns chainsMapped count. Params: name, packagePath?, sourceRig?, targetRig?, autoMapChains? (default true) (#246) |
read_ik_retargeter | Read IKRetargeter: source/target rigs and chain mappings. Params: assetPath (#246) |
set_anim_blueprint_skeleton | Set target skeleton on AnimBP. Params: assetPath, skeletonPath |
read_bone_track | Read bone transform samples from AnimSequence. Params: assetPath, boneName, frames?: [int] |
create_pose_search_database | Create a PoseSearchDatabase asset (motion matching). Params: name, packagePath?, schemaPath? |
set_pose_search_schema | Set the Schema on an existing PoseSearchDatabase. Params: assetPath, schemaPath |
add_pose_search_sequence | Append an AnimSequence/AnimComposite/AnimMontage/BlendSpace to a PoseSearchDatabase. Params: assetPath, sequencePath |
build_pose_search_index | Build (or rebuild) the search index. Params: assetPath, wait? (default true) |
read_pose_search_database | Inspect a PoseSearchDatabase: schema, animation entries, cost biases, tags. Params: assetPath |
set_sequence_properties | Batch-set properties on AnimSequence assets. If a path is a Montage and resolveFromMontages is true (default), resolves to its first AnimSequence. Params: assetPaths[], properties(enableRootMotion?, forceRootLock?, useNormalizedRootMotionScale?, rootMotionRootLock?), resolveFromMontages? |
bake_root_motion_from_bone | Bake delta translation from a source bone (e.g. pelvis) onto the root bone across the whole sequence; compensates the source bone so world-space position is unchanged. Params: `assetPath, sourceBone, rootBone? (default 'root'), axes? (default ['x','y']), interpolation? ('linear'\ |
get_bone_transform | Read a bone or socket transform on a live actor's SkeletalMeshComponent. Wraps GetBoneTransform / GetSocketTransform. Params: `actorLabel, boneName (or socket name), componentName? (default: CharacterMesh0 / Mesh / first SK component), space? (world\ |
list_bones | List bones in a live actor's SkeletalMeshComponent ref skeleton (name, index, parent). Params: actorLabel, componentName? (#420) |
rebind_leader_pose | Re-bind every secondary SkeletalMeshComponent on an actor to a body component (default CharacterMesh0 / Mesh). One-call fix for the 'character explodes after rotating the actor' failure mode. Params: actorLabel, bodyComponent? (#419) |
preview_animation | Toggle bUpdateAnimationInEditor + VisibilityBasedAnimTickOption=AlwaysTickPoseAndRefreshBones on every SkeletalMeshComponent of an actor. Bypasses the 'cannot be edited on templates' guard for level instances. Params: actorLabel, enabled (#419/#420) |
landscape
Landscape terrain: info, layers, sculpting, painting, materials, heightmap import.
| Action | Description |
|---|---|
get_info | Get landscape setup |
list_layers | List paint layers |
sample | Sample height/layers. Params: x, y |
list_splines | Read landscape splines |
get_component | Inspect component. Params: componentIndex |
set_material | Set landscape material. Params: materialPath |
add_layer_info | Register paint layer (creates LayerInfo asset + binds to active landscape). Params: layerName, packagePath?, weightBlended? |
create_layer_info | Standalone LayerInfo asset creation - no landscape required. Params: layerName, name? (default LI_[layerName]), packagePath? (default /Game/Landscape/LayerInfos), physMaterial? (asset path), hardness? (#251) |
create | Spawn a new ALandscape with a flat heightmap. Defaults match the Editor's Landscape Mode 'create new' (8x8 components, 63 quads/subsection, 2 subsections/component = 1016x1016 quads). Params: `location? (Vec3), scale? (Vec3, default 100,100,100), componentCountX? (default 8), componentCountY? (default 8), subsectionSizeQuads? (one of 7\ |
get_material_usage_summary | Per-proxy summary: landscape/hole material paths + component/grass/nanite counts (#150) |
pcg
Procedural Content Generation: graphs, nodes, connections, execution, volumes.
| Action | Description |
|---|---|
list_graphs | List PCG graphs. Params: directory?, recursive? |
read_graph | Read graph structure. Params: assetPath |
read_node_settings | Read node settings. Params: assetPath, nodeName |
get_components | List PCG components in level |
get_component_details | Inspect PCG component. Params: actorLabel |
create_graph | Create graph. Params: name, packagePath? |
add_node | Add node. Params: assetPath, nodeType, nodeName? |
connect_nodes | Wire nodes. Params: assetPath, sourceNode, sourcePin, targetNode, targetPin |
disconnect_nodes | Remove a wired edge between two PCG nodes. Params: assetPath, sourceNode, targetNode, sourcePin? (default: any), targetPin? (default: any) |
set_node_settings | Set node params. Params: assetPath, nodeName, settings |
set_static_mesh_spawner_meshes | Populate weighted MeshEntries on a PCGStaticMeshSpawner node (#145). Params: assetPath, nodeName, entries=[(mesh, weight?)], replace? (default true) |
remove_node | Remove node. Params: assetPath, nodeName |
execute | Regenerate PCG. Params: actorLabel |
force_regenerate | Force a stuck PCG component to regenerate (clears graph ref, re-sets, cleanup+generate). Params: actorLabel (#146) |
cleanup | Cleanup a PCG component (remove spawned content). Params: actorLabel, removeComponents? (default true) (#146) |
toggle_graph | Toggle a PCG component's graph assignment to force reinit (no generate). Params: actorLabel, graphPath? (#146) |
add_volume | Place PCG volume. Params: graphPath, location?, extent? |
import_graph | Bulk-author a PCG graph from JSON. Params: assetPath, nodes=[(name,class,posX?,posY?,settings?)], connections=[(from,fromPin?,to,toPin?)], replace? (default false) |
export_graph | Export a PCG graph as JSON. Params: assetPath, includeSettings? (default true) |
foliage
Foliage painting, types, sampling, and settings.
| Action | Description |
|---|---|
list_types | List foliage types in level |
get_settings | Read foliage type settings. Params: foliageTypeName |
sample | Query instances in region. Params: center, radius, foliageType? |
create_type | Create foliage type from mesh. Params: meshPath, name?, packagePath? |
set_settings | Modify type settings. Params: foliageTypeName, settings |
niagara
Niagara VFX: systems, emitters, spawning, parameters, and graph authoring.
| Action | Description |
|---|---|
list | List Niagara assets. Params: directory?, recursive? |
get_info | Inspect system. Params: assetPath |
spawn | Spawn VFX as a transient component (GC's before offscreen capture). For a findable preview use spawn_actor. Params: systemPath, location, rotation?, label? |
spawn_actor | Spawn a PERSISTENT, labeled NiagaraActor in the editor world (findable, re-activatable, survives capture - unlike spawn). Assigns the system and activates. Params: systemPath, location?, rotation?, label?, activate? (default true) (#537) |
reactivate | Reset + reactivate the NiagaraComponent on a placed actor (replay a burst before capturing). Params: actorLabel (#537) |
set_parameter | Set parameter. Params: actorLabel, parameterName, value, parameterType? |
create | Create system. Params: name, packagePath? |
create_emitter | Create Niagara emitter. Params: name, packagePath?, templatePath? |
add_emitter | Add emitter to system. Params: systemPath, emitterPath |
list_emitters | List emitters in system. Params: systemPath |
set_emitter_property | Set emitter property. Params: systemPath, emitterName?, propertyName, value |
list_modules | List Niagara modules. Params: directory? |
get_emitter_info | Inspect emitter. Params: assetPath |
list_renderers | List renderers on an emitter. Params: systemPath, emitterName?, emitterIndex? |
add_renderer | Add renderer (sprite/mesh/ribbon or full class). Params: systemPath, rendererType, emitterName?, emitterIndex? |
remove_renderer | Remove renderer by index. Params: systemPath, rendererIndex, emitterName?, emitterIndex? |
set_renderer_property | Set renderer bool/number/string property. Params: systemPath, rendererIndex, propertyName, value, emitterName?, emitterIndex? |
inspect_data_interfaces | List user-scope data interfaces. Params: systemPath |
create_system_from_spec | Declaratively create a system + emitters. Params: name, packagePath?, emitters?:[(path)] |
get_compiled_hlsl | Read GPU compute script info for an emitter. Params: systemPath, emitterName?, emitterIndex? |
list_system_parameters | List user-exposed system parameters. Params: systemPath |
list_module_inputs | List modules + their input pins for an emitter. Params: `systemPath, emitterName?, emitterIndex?, stackContext? (ParticleSpawn\ |
set_module_input | Set literal default on a module input pin. Params: systemPath, moduleName, inputName, value, emitterName?, emitterIndex?, stackContext? |
list_static_switches | List static switch inputs on a module. Params: systemPath, moduleName, emitterName?, emitterIndex?, stackContext? |
set_static_switch | Set static switch value on a module's function call node. Params: systemPath, moduleName, switchName, value, emitterName?, emitterIndex?, stackContext? |
create_module_from_hlsl | Create a NiagaraScript module backed by a custom HLSL node. Params: name, hlsl, packagePath?, inputs?:[(name,type)], outputs?:[(name,type)] |
create_scratch_module | Create empty Niagara scratch module. Params: name, packagePath?, inputs?:[(name,type)], outputs?:[(name,type)] (#185) |
batch | Run a sequence of niagara operations against the bridge in order. Fails fast on the first error (returns results up to that point + error). Params: ops:[(action, params)] where action is any niagara subaction listed above |
audio
Audio: sound assets, playback, ambient sounds, SoundCues, MetaSounds.
| Action | Description |
|---|---|
list | List sound assets. Params: directory?, recursive? |
play_at_location | Play sound. Params: soundPath, location, volumeMultiplier?, pitchMultiplier? |
spawn_ambient | Place ambient sound. Params: soundPath, location, label? |
create_cue | Create SoundCue. Params: name, packagePath?, soundWavePath? |
create_metasound | Create MetaSoundSource. Params: name, packagePath? |
widget
UMG Widget Blueprints, Editor Utility Widgets, and Editor Utility Blueprints.
| Action | Description |
|---|---|
read_tree | Read widget hierarchy. Params: assetPath |
get_details | Inspect widget (curated subset). Params: assetPath, widgetName |
get_properties | Full reflected property dump for a widget - every UPROPERTY (RenderOpacity, Visibility, ColorAndOpacity, Border padding/colors, Image brush TintColor/ImageSize, fonts, etc.) plus the slot block, for diagnosing visual bugs get_details omits. Pass includeSubtree to also dump children (#547). Params: assetPath, widgetName, includeSubtree? |
list_bindings | List designer property bindings on a WidgetBlueprint (the UE 5.7 Python API keeps them protected). Returns {widgetName, propertyName, functionName, bindingType}. Optional filterWidgetName/filterProperty (#530). Params: assetPath, filterWidgetName?, filterProperty? |
clear_binding | Remove designer binding(s) matching widgetName (and optional propertyName) from a WidgetBlueprint without opening the editor. Idempotent (#530). Params: assetPath, widgetName, propertyName? |
set_property | Set widget property. Slot struct props take UE struct text that persists every field - Slot.Size=(Value=1.0,SizeRule=Fill), Slot.Padding=(Left=8,Top=8,Right=8,Bottom=8) - or a nested field path like Slot.Size.Value / Slot.Padding.Left; an invalid value errors instead of silently writing 0 (#532). Params: assetPath, widgetName, propertyName, value |
list | List Widget BPs. Params: directory?, recursive? |
read_animations | Read UMG animations. Params: assetPath |
create | Create Widget BP. Params: name, packagePath?, parentClass? |
create_utility_widget | Create editor utility widget. Params: name, packagePath? |
run_utility_widget | Open editor utility widget. Params: assetPath |
create_utility_blueprint | Create editor utility blueprint. Params: name, packagePath? |
run_utility_blueprint | Run editor utility blueprint. Params: assetPath |
add_widget | Add widget to widget tree. Params: assetPath, widgetClass, widgetName?, parentWidgetName? |
remove_widget | Remove widget from tree. Params: assetPath, widgetName |
move_widget | Reparent widget. Params: assetPath, widgetName, newParentWidgetName |
set_root | Replace WBP root with an existing widget by name (#365). Params: assetPath, widgetName |
wrap_root | Wrap the current root in a new panel widget (UMG 'Wrap With'). Params: assetPath, wrapperClass (must be a UPanelWidget subclass), wrapperName? (#365) |
list_classes | List available widget classes |
list_runtime | (#160) List live UUserWidget instances in the PIE world. Params: classFilter?, namePrefix?, viewportOnly? |
get_runtime | (#160) Inspect a live PIE widget tree with text/visibility/brush/percent values. Params: `widgetName? \ |
get_runtime_delegates | (#161) Read delegate binding state on a live PIE widget. Params: widgetName, className? |
editor
Editor commands, Python execution, PIE, undo/redo, hot reload, viewport, performance, sequencer, build pipeline, logs, editor control.
| Action | Description |
|---|---|
start_editor | Launch Unreal Editor with the current project and reconnect bridge |
stop_editor | Close Unreal Editor gracefully |
restart_editor | Stop then start the editor |
build_project | Build the project's C++ code using Unreal Build Tool. Editor should be stopped first |
execute_command | Run console command. Params: command |
execute_python | Run Python in editor. Params: code |
run_python_file | Run a Python file from disk with file/name populated (#142). Params: filePath, args? |
set_property | Set UObject property. Params: objectPath, propertyName, value |
play_in_editor | PIE control. Params: `pieAction (start\ |
get_runtime_value | Read PIE actor property. Params: actorLabel, propertyName (supports dotted paths: component.field or component.struct.field for nested reads on component subobjects, #344/#381) |
get_pie_pawn | Resolve the controlled pawn in the active PIE world. Params: playerIndex? (default 0) |
invoke_function | Call a BlueprintCallable / Exec UFUNCTION on a target actor or one of its components. Params: `actorLabel, functionName, component? (component subobject name; redirects target from the actor to that component, #382), args? (object), actorArgs? (object mapping UObject* parameter name to actor label, resolved against live actors in the active world; #383), world? (editor\ |
invoke_static_function | Call a static UFUNCTION on a UBlueprintFunctionLibrary (no actor instance). invoke_function needs an actor/component target; this targets the library class CDO instead, so it reaches static _BlueprintOnly libraries (Voxel sculpt/query/stamp), GeometryScript, Kismet math, any function library. Params: `className (short name or /Script/Module.Class path), functionName, args? (name -> JSON value, same marshalling as invoke_function), actorArgs? (name -> actor label for UObject params that are actors, e.g. the sculpt actor), worldContextParam? (name of a UObject* param to fill with the editor/PIE world; auto-detected for params named WorldContextObject), world? (editor\ |
list_function_libraries | Enumerate UBlueprintFunctionLibrary subclasses on this build. Filter by name (case-insensitive substring, e.g. 'GeometryScript' / 'Kismet' / 'Animation'). Returns name, module, and (by default) every static BlueprintCallable function on the library with its tooltip. Use to discover what's available for editor.invoke_function (#455). Params: pattern?, includeFunctions? |
set_pie_time_scale | Fast-forward PIE game time. Params: factor (>0) |
hot_reload | Hot reload C++ |
undo | Undo last transaction |
redo | Redo last transaction |
get_perf_stats | Editor performance stats |
run_stat | Run stat command. Params: command |
set_scalability | Set quality. Params: level |
capture_screenshot | Screenshot. Params: `filename?, resolution?, target? (auto\ |
capture_scene_png | Headless PNG screenshot via SceneCapture2D (works unfocused, guaranteed RGBA8 LDR). Params: outputPath, location?, rotation?, width? (default 1280), height? (default 720), fov? (default 90) (#148) |
set_realtime | Toggle realtime update on the level editor viewports so the editor-world sim (Niagara, anims) ticks - otherwise capture_scene_png renders an unticked, empty sim. Params: enabled (default true) (#537) |
get_viewport | Get viewport camera |
hit_test_viewport_pixel | Ray-cast from a screen pixel through the active editor viewport and return the first hit. Builds the ray from the live viewport's projection matrix (no FOV/aspect guessing). Returns hit + actorLabel/actorClass/componentName/componentClass/materialPath/location/impactPoint/normal/distance/faceIndex/boneName/physicalMaterial. Params: x, y (pixel coords), width? height? (override viewport size when picking from a different-resolution screenshot), maxDistance? (default 200000), ignoreActors? (array of actor labels) (#418) |
get_runtime_values | Bulk runtime read across the active world. For each actor/component matching classFilter, resolves every path against the (actor|component) root and returns rows of {actorLabel, actorClass, componentName?, componentClass?, values, errors?}. Paths support property hops, sub-object hops, and zero-arg BlueprintCallable getter calls at any segment (e.g. 'PowerConnector.GetRequired' reaches a UFUNCTION on a UObject sub-object). classFilter matches actor class OR component class - omit to match everything. World defaults to PIE if running, else editor. Params: `classFilter?, paths[], world? (editor\ |
set_viewport | Set viewport camera. Params: location?, rotation? |
focus_on_actor | Focus on actor. Params: actorLabel |
create_sequence | Create Level Sequence. Params: name, packagePath? |
get_sequence_info | Read sequence. Params: assetPath, includeSectionDetails? (attach sockets, first transform key values per track) |
add_sequence_track | Add an empty track. Params: assetPath, trackType, actorLabel? |
add_sequence_section | Add a section to a track (creating the track if needed), set its start/end in seconds, and for a CameraCut track bind it to a camera. Returns the section index + channel names to key. Params: `sequencePath, trackType (Transform\ |
set_sequence_keyframes | Add keyframes to a section channel. Transform channels: Location.X/Y/Z, Rotation.X/Y/Z (or friendly x/y/z, yaw/pitch/roll); Fade/Float: the float channel. Params: `sequencePath, trackType, actorLabel?, sectionIndex? (default 0), channel, keyframes ([(seconds, value)]), interpolation? (cubic\ |
set_sequence_playback_range | Set a Level Sequence's playback range in seconds. Params: sequencePath, startSeconds, endSeconds (#548) |
play_sequence | Play/stop/pause sequence. Params: assetPath, sequenceAction |
build_all | Build all (geometry, lighting, paths, HLOD) |
build_geometry | Rebuild BSP geometry |
build_hlod | Build HLODs |
validate_assets | Run data validation. Params: directory? |
get_build_status | Get build/map status |
cook_content | Cook content. Params: platform? |
get_log | Read output log. Params: maxLines?, filter?, category? |
search_log | Search log. Params: query |
get_message_log | Read message log. Params: logName? |
list_crashes | List crash reports |
get_crash_info | Get crash details. Params: crashFolder |
check_for_crashes | Check for recent crashes |
set_dialog_policy | Auto-respond to dialogs matching a pattern. Params: pattern, response |
clear_dialog_policy | Clear dialog policies. Params: pattern? |
get_dialog_policy | Get current dialog policies |
list_dialogs | List active modal dialogs |
respond_to_dialog | Click a button on the active modal dialog. Params: buttonIndex?, buttonLabel? |
open_asset | Open asset in its editor. Params: assetPath |
reload_bridge | Hot-reload Python bridge handlers from disk |
save_dirty | Flush every dirty package and return a per-package saved/failed map. Use after multi-step CDO/component edits when set_class_default leaves the asset dirty without persisting (#378). Params: includeMaps? (default true), includeContent? (default true) |
configure_pie | Set ULevelEditorPlaySettings - multi-client PIE, net mode, single-process flag. Params: `numClients?, netMode? (standalone\ |
get_pie_config | Read current ULevelEditorPlaySettings (numClients, netMode, single-process, separate-server) (#384) |
list_dirty_packages | Enumerate currently-dirty content + map packages (#340) |
reflection
UE reflection: classes, structs, enums, gameplay tags.
| Action | Description |
|---|---|
reflect_class | Reflect UClass. Params: className, includeInherited? |
reflect_struct | Reflect UScriptStruct. Params: structName |
reflect_enum | Reflect UEnum. Params: enumName |
list_classes | List classes. Params: parentFilter?, limit? |
list_tags | List gameplay tags. Params: filter? |
create_tag | Create gameplay tag. Params: tag, comment? |
create_enum | Create UUserDefinedEnum asset, optionally seeded with entries. Params: `name, packagePath?, entries?: (string\ |
set_enum_entries | Replace entries on an existing UUserDefinedEnum. Params: assetPath, entries[] (#274) |
gameplay
Gameplay systems: physics, collision, navigation, input, behavior trees, AI (EQS, perception, State Trees, Smart Objects), game framework.
| Action | Description |
|---|---|
set_collision_profile | Set collision preset. Params: actorLabel, profileName |
set_simulate_physics | Toggle physics. Params: actorLabel, simulate |
set_collision_enabled | Set collision mode. Params: actorLabel, collisionEnabled |
set_collision | Unified collision authoring for a placed actor (actorLabel) or a Blueprint component template (assetPath+componentName). Apply any of: collisionProfile, collisionEnabled (NoCollision|QueryOnly|PhysicsOnly|QueryAndPhysics), objectType (channel name), responseToAllChannels (Block|Overlap|Ignore), responses ({channel: Block|Overlap|Ignore}). Profile is applied first, then overrides. componentName optional for actors (defaults to all primitive components), required for Blueprint templates (#545) |
set_physics_properties | Set mass/damping/gravity. Params: actorLabel, mass?, linearDamping?, angularDamping?, enableGravity? |
rebuild_navigation | Rebuild navmesh |
find_nav_path | Synchronous nav-path query between two world points. Returns valid/partial/length plus the polyline. The standard 'why doesn't my AI move?' diagnostic. Params: start (Vec3), end (Vec3), pathfindingContext? (actorLabel - uses its agent + filter) (#424) |
list_nav_invokers | Enumerate actors carrying a NavigationInvokerComponent + their tile generation/removal radii. Diagnoses 'no navmesh in this region' caused by missing or mis-sized invokers (#424) |
get_navmesh_info | Query nav system |
project_to_nav | Project point to navmesh. Params: location, extent? |
spawn_nav_modifier | Place nav modifier. Params: location, extent?, areaClass? |
create_input_action | Create InputAction. Params: name, packagePath?, valueType? |
create_input_mapping | Create InputMappingContext. Params: name, packagePath? |
list_input_assets | List input assets. Params: directory?, recursive? |
read_imc | Read InputMappingContext mappings. Params: imcPath |
list_input_mappings | Alias for read_imc. List key→action bindings with triggers/modifiers. Params: imcPath |
add_imc_mapping | Add key mapping to IMC. Params: imcPath, inputActionPath, key |
set_mapping_modifiers | Set modifiers/triggers on an IMC mapping. Params: imcPath, mappingIndex?, modifiers?, triggers? |
remove_imc_mapping | Remove an IMC mapping. Params: `imcPath, mappingIndex? \ |
set_imc_mapping_key | Rebind an IMC mapping to a new key. Params: `imcPath, newKey, mappingIndex? \ |
set_imc_mapping_action | Retarget an IMC mapping to a different InputAction. Params: `imcPath, newInputActionPath, mappingIndex? \ |
list_behavior_trees | List behavior trees. Params: directory?, recursive? |
get_behavior_tree_info | Inspect behavior tree (top-level + blackboard). Params: assetPath |
read_behavior_tree_graph | Walk BT tree: composites, tasks, decorators, services with blackboard keys. Params: assetPath |
create_blackboard | Create Blackboard. Params: name, packagePath? |
add_blackboard_key | Add a typed key to a Blackboard asset. Params: `blackboardPath, keyName, keyType (Bool\ |
remove_blackboard_key | Remove a key from a Blackboard asset by name. Idempotent. Params: blackboardPath, keyName (#469) |
set_blackboard_parent | Set Parent on a BlackboardData asset (canonical UE child-of-parent pattern). Pass parentPath="None" or omit to clear. autoPruneDuplicateKeys (default true) removes own-keys that the parent chain already defines so the BT compiler accepts the child (#469) |
read_blackboard | Read a Blackboard asset: parent path, ownKeys, inheritedKeys (walks the parent chain). Params: blackboardPath (#469) |
list_bt_node_classes | Enumerate every concrete BehaviorTree node class on this build (composites, tasks, decorators, services). Filter by kind to narrow. Useful for discovering plugin-supplied decorator/task classes without grepping engine + plugin source. Params: `kind? ('composite'\ |
set_behavior_tree_blackboard | Rebind a BehaviorTree asset's BlackboardAsset reference. Params: behaviorTreePath, blackboardPath |
create_behavior_tree | Create behavior tree. Params: name, packagePath?, blackboardPath? |
create_eqs_query | Create EQS query. Params: name, packagePath? |
list_eqs_queries | List EQS queries. Params: directory? |
add_perception | Add AIPerceptionComponent. Params: blueprintPath, senses? |
configure_sense | Add + configure an AI perception sense config on the blueprint's AIPerceptionComponent. Params: `blueprintPath, senseType (Sight\ |
create_state_tree | Create StateTree. Params: name, packagePath? |
list_state_trees | List StateTrees. Params: directory? |
add_state_tree_component | Add StateTreeComponent. Params: blueprintPath |
create_smart_object_def | Create SmartObjectDefinition. Params: name, packagePath? |
add_smart_object_component | Add SmartObjectComponent. Params: blueprintPath |
add_smart_object_slot | Append a FSmartObjectSlotDefinition to a SmartObjectDefinition's Slots array. Params: assetPath, name?, offset? ((x,y,z)), rotation? ((pitch,yaw,roll)), tags? (array) |
set_smart_object_slot | Mutate an existing slot's offset/rotation/tags. Params: assetPath, slotIndex, offset? ((x,y,z)), rotation? ((pitch,yaw,roll)), tags? (array) |
remove_smart_object_slot | Remove a slot by index. Idempotent: out-of-range returns alreadyDeleted=true. Params: assetPath, slotIndex (#416) |
list_smart_object_slots | List slots on a SmartObjectDefinition with index, offset, rotation, and raw text. Params: assetPath (#416) |
add_smart_object_slot_behavior | Attach a behavior definition (UBehaviorDefinition asset or class) to a slot's BehaviorDefinitions array. Pass instanceProperties to seed UPROPERTYs on a freshly-spawned class-instance. Params: assetPath, slotIndex, behaviorClass (asset path or class path), instanceProperties? (#416) |
create_game_mode | Create GameMode BP. Params: name, packagePath?, parentClass?, defaults? |
create_game_state | Create GameState BP. Params: name, packagePath?, parentClass? |
create_player_controller | Create PlayerController BP. Params: name, packagePath?, parentClass? |
create_player_state | Create PlayerState BP. Params: name, packagePath? |
create_hud | Create HUD BP. Params: name, packagePath? |
set_world_game_mode | Set level GameMode override. Params: gameModeClass (or legacy gameModePath) |
get_framework_info | Get level framework classes |
get_navmesh_details | Read RecastNavMesh generation params (cellSize, agentHeight, maxStepHeight, etc.) (#163) |
gas
Gameplay Ability System: abilities, effects, attribute sets, cues.
| Action | Description |
|---|---|
add_asc | Add AbilitySystemComponent. Params: blueprintPath, componentName? |
create_attribute_set | Create AttributeSet BP. Params: name, packagePath? |
add_attribute | Add attribute to set. Params: attributeSetPath, attributeName, defaultValue? |
create_ability | Create GameplayAbility BP. Params: name, packagePath?, parentClass? |
set_ability_tags | Set tags on ability. Params: abilityPath, ability_tags?, cancel_abilities_with_tag?, activation_required_tags?, activation_blocked_tags? |
create_effect | Create GameplayEffect BP. Params: name, packagePath?, durationPolicy? |
set_effect_modifier | Add modifier. Params: effectPath, attribute, operation?, magnitude? |
create_cue | Create GameplayCue. Params: name, packagePath?, cueType? |
get_info | Inspect GAS setup. Params: blueprintPath |
set_asc_defaults | Wire an AttributeSet onto a Blueprint's ASC component (DefaultStartingData) so attributes exist at runtime. Params: blueprintPath, attributeSet (content path or class name), componentName?, initDataTable? (starting values) |
apply_effect | Apply a GameplayEffect to a live actor's ASC (agnostic stat/damage stimulus - uses the game's own effect). Params: `actorLabel, effectClass (content path or class name), level?, setByCaller? ((tag-or-name: magnitude)), world? (auto\ |
set_attribute | Set a gameplay attribute's base value on a live actor's ASC (recalculates CurrentValue through the aggregator). Params: `actorLabel, attribute (Health \ |
get_attribute | Read gameplay attribute base + current values on a live actor's ASC. Omit attribute to list all. Params: actorLabel, attribute?, world? |
init_asc | Initialize a live actor's ASC (InitAbilityActorInfo) and optionally instantiate an AttributeSet so attributes are live - the runtime setup step for testing a bridge-authored GAS actor. Params: actorLabel, attributeSet? (content path or class name), world? |
networking
Networking and replication: actor replication, property replication, net relevancy, dormancy.
| Action | Description |
|---|---|
set_replicates | Enable actor replication. Params: blueprintPath, replicates? |
set_property_replicated | Mark variable as replicated. Params: blueprintPath, propertyName, replicated?, replicationCondition?, repNotify? |
configure_net_frequency | Set update frequency. Params: blueprintPath, netUpdateFrequency?, minNetUpdateFrequency? |
set_dormancy | Set net dormancy. Params: blueprintPath, dormancy |
set_net_load_on_client | Control client loading. Params: blueprintPath, loadOnClient? |
set_always_relevant | Always network relevant. Params: blueprintPath, alwaysRelevant? |
set_only_relevant_to_owner | Only relevant to owner. Params: blueprintPath, onlyRelevantToOwner? |
configure_cull_distance | Net cull distance. Params: blueprintPath, netCullDistanceSquared? |
set_priority | Net priority. Params: blueprintPath, netPriority? |
set_replicate_movement | Replicate movement. Params: blueprintPath, replicateMovement? |
get_info | Get networking info. Params: blueprintPath |
demo
Neon Shrine demo scene builder and cleanup.
| Action | Description |
|---|---|
step | Execute demo step. Params: stepIndex? |
cleanup | Remove demo assets and actors. Switches editor to /Game/MCP_Home before deleting so the editor is never left on an Untitled map |
go_home | Switch the editor to /Game/MCP_Home (creating it on first use). Use this before any operation that would leave the editor on an Untitled map |
feedback
Submit feedback to improve ue-mcp when native tools fall short and execute_python was used as a workaround.
| Action | Description |
|---|---|
submit | Submit feedback about a tool gap. Blocks on an MCP elicitation prompt that asks the USER (not the agent) to approve or decline the exact payload before anything is posted to GitHub |
statetree
StateTree asset editing: read, modify states/tasks/conditions/transitions/bindings/evaluators/global tasks/colors/state parameters/root parameters, compile and validate.
| Action | Description |
|---|---|
read | Full dump of a StateTree asset: state hierarchy (with description, tag, customTickRate, color), tasks, conditions, transitions, evaluators, global tasks, root params, bindings. Params: assetPath |
list_states | List all states with IDs and paths. Params: assetPath |
add_state | Add child state. Params: `assetPath, stateId? (parent GUID, omit for root), name, stateType? (State\ |
remove_state | Remove a state by ID. Params: assetPath, stateId |
set_state_property | Set a property on a state. Params: `assetPath, stateId, propertyName (name\ |
clear_state_nodes | Remove all tasks/conditions/transitions from a state. Params: assetPath, stateId |
add_task | Add a task to a state. Params: assetPath, stateId, structType (C++ struct name e.g. FMyStateTreeTask or an engine-shipped task like FStateTreeRunParallelStateTreesTask), instanceProperties? |
add_enter_condition | Add an enter condition to a state. Params: `assetPath, stateId, structType (C++ struct name), instanceProperties?, operand? (And\ |
remove_enter_condition | Remove an enter condition by index. Params: assetPath, stateId, conditionIndex |
remove_task | Remove a task by index. Params: assetPath, stateId, taskIndex |
set_task_instance_property | Set a property on a task's instance data. Params: assetPath, stateId, taskIndex, propertyName, value |
set_task_property | Set a property on the task's node struct (FStateTreeTaskBase-level: bConsideredForCompletion, bTaskEnabled, bShouldStateChangeOnReselect). Distinct from set_task_instance_property which targets instance data. Params: assetPath, stateId, taskIndex, propertyName, value (string-encoded e.g. 'true'/'false') |
add_transition | Add a transition to a state. Params: `assetPath, stateId, trigger (OnStateCompleted\ |
add_transition_condition | Add a condition to an existing transition. Params: assetPath, stateId, transitionIndex, structType, instanceProperties?, operand? |
remove_transition | Remove a transition by index. Params: assetPath, stateId, transitionIndex |
add_binding | Add a property binding. Params: assetPath, sourceStructId, sourcePath, targetStructId, targetPath |
remove_binding | Remove a property binding. Params: assetPath, targetStructId, targetPath |
list_bindings | List all property bindings. Params: assetPath, structId? (filter) |
add_evaluator | Add an evaluator to the StateTree (tree-level). Params: assetPath, structType (must derive from FStateTreeEvaluatorBase), instanceProperties? |
remove_evaluator | Remove an evaluator by node ID. Params: assetPath, nodeId |
set_evaluator_instance_property | Set a property on an evaluator's instance data. Params: assetPath, nodeId, propertyName, value |
set_evaluator_property | Set a property on the evaluator's node struct (FStateTreeEvaluatorBase-level). Params: assetPath, nodeId, propertyName, value |
add_global_task | Add a global task to the StateTree (tree-level). Params: assetPath, structType (must derive from FStateTreeTaskBase), instanceProperties? |
remove_global_task | Remove a global task by node ID. Params: assetPath, nodeId |
set_global_task_instance_property | Set a property on a global task's instance data. Params: assetPath, nodeId, propertyName, value |
set_global_task_property | Set a property on a global task's node struct (FStateTreeTaskBase-level). Params: assetPath, nodeId, propertyName, value |
list_colors | List all color palette entries for a StateTree. Params: assetPath |
add_color | Add a new color to the StateTree palette. Params: assetPath, displayName, color? (FLinearColor string e.g. '(R=1.0,G=0.0,B=0.0,A=1.0)') |
list_state_parameters | List parameters defined on a state. Params: assetPath, stateId |
add_state_parameter | Add a parameter to a state's property bag. Rejects fixed-layout (linked) states. Params: `assetPath, stateId, paramName, paramType (Bool\ |
remove_state_parameter | Remove a parameter from a state's property bag by name. Rejects fixed-layout (linked) states. Params: assetPath, stateId, paramName |
set_state_parameter | Set the value of an existing state parameter. On fixed-layout states, also marks the parameter as overridden. Params: assetPath, stateId, paramName, value |
set_root_parameters | Define root parameters (property bag). Params: `assetPath, parameters[] ((name, type)) where type is float\ |
compile | Compile a StateTree asset. Returns success, errors[], warnings[]. Params: assetPath |
validate | Validate a StateTree asset without compiling. Params: assetPath |
plugins
Introspect npm-distributed plugins that contribute actions into other categories. Read-only.
| Action | Description |
|---|---|
list | Every plugin loaded from ue-mcp.yml: name, version, prefix, status, and injected actions |
describe | Full detail for one plugin including knowledge files and flows. Params: name |