Project Settings

Project Settings Skill

🔀 Registered settings moved to the engine. Category-based registered-setting access (list_categories / list_settings / get_setting / set_setting / set_category_settings_from_json) is now Unreal 5.8's native ConfigSettingsToolset — reach it with call_tool (run describe_toolset on ConfigSettingsToolset for its actions/params). VibeUE's ProjectSettingsService was trimmed to the delta the engine doesn't cover: discover_settings_classes + direct INI read/write (get_ini_value / set_ini_value / *_ini_array / list_ini_sections / list_ini_keys) + config save, plus set_settings_property / get_settings_property for one property of a settings class by name. Use those from execute_python_code as shown below.

Critical Rules

⚠️ EditorStyleSettings is NOT a Python Class

EditorStyleSettings is not discoverable via discover_python_class('unreal.EditorStyleSettings') — it returns PYTHON_CLASS_NOT_FOUND. Reach it through the engine ConfigSettingsToolset as a settings category (via call_tool), or write its values directly via raw INI:

# ❌ WRONG — will fail
discover_python_class('unreal.EditorStyleSettings')  # NOT FOUND

# ✅ CORRECT — engine ConfigSettingsToolset (registered settings) via call_tool, OR the class by name:
result = unreal.ProjectSettingsService.set_settings_property(
    "EditorStyleSettings", "AssetEditorOpenLocation", "MainWindow")

set_ini_value writes the file you name: a bare name resolves to the project Config/ folder ("DefaultGame.ini" → Config/DefaultGame.ini), an absolute path is used as-is, and the path must end in .ini. A bare "EditorPerProjectUserSettings.ini" therefore writes Config/EditorPerProjectUserSettings.ini, a file no config hierarchy reads. An absolute path does reach a user-layer file under Saved/Config/<Platform>Editor/, but the editor keeps those files in memory and rewrites them from memory when it saves its config (at the latest when it exits), which can silently drop a direct write. Change user settings (editor preferences such as EditorStyleSettings) with set_settings_property, which edits the editor's in-memory copy and saves it.

⚠️ Category vs Raw INI

Named registered-setting categories (general, maps, EditorStyleSettings, etc.) are handled by the engine ConfigSettingsToolset. From VibeUE you instead address settings by their INI section / key / file:

⚠️ Map Paths Must Be Full Asset Paths

# WRONG - folder path
"/Game/Variant_Horror.Variant_Horror"

# CORRECT - full map asset path  
"/Game/Variant_Horror/Lvl_Horror.Lvl_Horror"

Always verify with does_asset_exist() before setting.

⚠️ Always Check Operation Results

The INI write methods return an FProjectSettingResult:

result = unreal.ProjectSettingsService.set_ini_value(
    "/Script/EngineSettings.GeneralProjectSettings", "ProjectName", "MyGame", "DefaultGame.ini")
if not result.success:
    print(f"Failed: {result.error_message}")

set_ini_value writes the key into the file on disk (the rest of the file, comments included, is kept), reloads that config branch, and reads the file back: success is false when the value did not land, and the file is then put back exactly as it was. A section or key containing a line break, a section containing ], and a path that does not end in .ini are refused before anything is written. A settings object read its config at startup, so it sees the new value after a restart (requires_restart is true); set_settings_property applies the value live as well.

get_ini_value, list_ini_keys and get_ini_array read the file on disk as it is now (one file, not the merged config hierarchy), so they see set_ini_value, set_settings_property and hand edits at once. get_ini_value returns the plain Key= line, resolved as GConfig resolves it; +Key= / .Key= array lines are not its value. get_ini_array returns the Key=, +Key= and .Key= lines in file order (-Key= removals and !Key=ClearArray are not values). For the merged value a settings object actually uses, read get_settings_property.

set_settings_property takes any loaded config class (CLASS_Config), not only the ones the Settings window lists, and saves it the way the Settings window does: a defaultconfig class to its project Default*.ini, a user-config class to its user file, any other class to its config branch under Saved/Config. The value applies live (PostEditChangeProperty runs, as for an edit in the details panel), so an engine or editor class changes behavior immediately. Per-object-config classes are refused.

set_ini_array works only on a settings class section (/Script/Module.Class), through set_settings_property: an array in a layered project file needs !Key=ClearArray / +Key= lines relative to the lower layers, which only a settings object writes correctly. It replaces the whole array. Each value is one element in Unreal text format: an element of a struct array is a struct literal and goes in as written; an element of a string array is passed as the plain string and quoted for you; any other element containing a space, comma, parenthesis or quote is quoted for you.