“Setting the parent of a transform which resides in a Prefab Asset is disabled to prevent data corruption” error is thrown when generating a new 3D Object with a Prefab selected

Steps to reproduce:

1. Create a new Unity project using the Universal 3D template
2. Open the Package Manager window
3. Install the AI Assistant package (com.unity.ai.assistant)
4. Generate a new 3D Object (GameObject > 3D Object > Generate 3D Object)
5. Close the "New Mesh" window
6. Select the newly generated Mesh Asset in the Project window
7. Repeat step 4
8. Observe the Console window

Actual results: “Setting the parent of a transform which resides in a Prefab Asset is disabled to prevent data corruption” error is thrown

Expected results: No errors are thrown

Reproducible with versions: 1.6.0-pre.1, 2.1.0-pre.1 (6000.0.70f1, 6000.3.11f1, 6000.4.0b12, 6000.5.0a8)

Tested on (OS): MacOS Silicon Tahoe 26.2

Notes:

• Does not reproduce when generating through the customizable toolbar, only through the GameObject menu