The Component Warning command is a passive guard that warns you before a new feature is created in the wrong place in an assembly. When enabled, it watches for feature-creation commands (sketches, solids, work geometry, patterns, and surfaces) and prompts you when the feature would be created directly in the root component, in a non-leaf component, or while a selection references a different component than the one you are editing. This helps keep assembly designs organized by ensuring features are authored inside the component they belong to.
The command is a toggle: turn it on to monitor placement, turn it off to work without prompts.
- Catch features that would be created directly in the root component, outside of any component.
- Catch features that reference a component other than the one currently being edited.
- Optionally catch features created in a non-leaf component (a component that still has child occurrences).
- Choose, per warning, to create the feature anyway, cancel the command, or silence the warning for the active document.
- Enable or disable the guard from PowerTools Settings in the QAT File menu.
- An Autodesk Fusion 3D Design must be active.
- The guard is active only in the Design (Solid) workspace; it automatically detaches in other workspaces.
- The active design must use Assembly or Hybrid design intent. Designs with Part intent are skipped, because features there are meant to be built directly in the root component.
- Open the QAT File menu (the file icon at the top-left of Fusion) and expand PowerTools Settings.
- Click Enable Component Warning. The menu item changes to Disable Component Warning while the guard is active.
- Continue modeling as usual. If you start a feature-creation command while editing the root component (or referencing another component), a warning dialog appears.
- In the warning dialog, choose one of the following:
- Yes — create the feature anyway. To avoid a duplicate prompt, the guard pauses briefly after this choice.
- No — stop warning for the active document for the rest of the session.
- Cancel — cancel the command so no feature is created.
- To turn the guard off entirely, open PowerTools Settings again and click Disable Component Warning.
Note: Documents silenced with No are remembered only for the current Fusion session. Reopening the document restores warnings.
While enabled and while the Solid workspace is active, the command listens to the Fusion commandStarting event. When a watched feature-creation command begins, the guard inspects the active edit target:
- If the active edit target is the root component, the feature would be created outside of any component.
- If only-leaf checking is enabled and the target component still has child occurrences, the feature would be created in a non-leaf component.
- If any current selection belongs to a different component than the one being edited, the feature would reference another component.
When any of these is true, the warning dialog is shown before the command runs. Choosing Cancel sets the starting command to canceled so it never executes.
The set of watched commands and the only-leaf option are defined at the top of commands/componentwarn/entry.py.
Component Warning is accessed from the QAT File menu › PowerTools Settings. The menu item label reflects the current state: Enable Component Warning when the guard is off, Disable Component Warning when it is on. The PowerTools Settings submenu is shared with other PowerTools add-ins and is created automatically on first use.
The following diagrams show how the Component Warning command interacts with Autodesk Fusion.
C4Context
title Component Warning – System Context
Person(user, "Design Engineer", "Autodesk Fusion user building a multi-component assembly")
System(addin, "PowerTools Assembly", "Autodesk Fusion add-in")
System_Ext(fusion, "Autodesk Fusion", "Host application and Python API (adsk.core, adsk.fusion)")
Rel(user, addin, "Toggles Component Warning; answers warning dialog")
Rel(addin, fusion, "Listens to commandStarting; inspects active edit object; cancels command on request")
C4Component
title Component Warning – Component View
Person(user, "Design Engineer")
Component(cmd, "componentwarn/entry.py", "PowerTools Command", "Registers the toggle, manages the commandStarting listener, evaluates placement, shows the warning")
Component(api_ui, "adsk.core.UserInterface", "Fusion API", "commandStarting event, activeSelections, messageBox")
Component(api_design, "adsk.fusion.Design", "Fusion API", "rootComponent, designIntent")
Component(api_comp, "adsk.fusion.Component", "Fusion API", "activeEditObject, occurrences, assemblyContext")
Rel(user, cmd, "Enables guard / answers dialog")
Rel(cmd, api_ui, "Subscribes to commandStarting; reads selections; shows warning")
Rel(cmd, api_design, "Checks designIntent and rootComponent")
Rel(cmd, api_comp, "Inspects active edit object and selection contexts")
sequenceDiagram
autonumber
actor User
participant Menu as QAT › PowerTools Settings
participant Cmd as Component Warning
participant API as Fusion API
User->>Menu: Click "Enable Component Warning"
Menu->>Cmd: command_execute fires
Cmd->>Cmd: _enabled = True; label → "Disable Component Warning"
Cmd->>API: Attach commandStarting listener
User->>API: Start a feature command (e.g. Extrude)
API->>Cmd: command_starting fires
Cmd->>API: Read designIntent, activeEditObject, selections
alt Feature lands in wrong place
Cmd->>User: Show warning (Yes / No / Cancel)
User-->>Cmd: Choice
alt Cancel
Cmd->>API: args.isCanceled = true
else No
Cmd->>Cmd: Silence active document
else Yes
Cmd->>Cmd: Start hold-off timer
end
else Placement is fine
Cmd-->>API: Do nothing (command proceeds)
end
Copyright © 2026 IMA LLC. All rights reserved.