How to reproduce:
1. Open the attached “IN-139905” project
2. Ensure you have Claude or Cursor installed with a license
3. Verify and configure MCP (see internal notes)
4. Navigate to Edit > Project Settings > AI > Unity MCP > Tools > Core
5. Activate the “Unity_ManageGameObject“ tool
6. Open the project in Cursor or Claude
7. Copy and paste the text below into Cursor
{
"action": "get_components",
"target": "Main Camera",
"search_method": "by_name",
"include_non_public_serialized": true
}
8: Run Cursor
9. Observe the crash
Reproducible with: 2.5.0-pre.2 (6000.6.0a4), 2.6.0-pre.1 (6000.4.5f1, 6000.5.0b6, 6000.6.0a4)
Could not test with: 2.5.0-pre.1 (6000.6.0a4) 2.6.0-pre.1 (6000.0.74f1, 6000.3.14f1), (would run forever but not crash)
Reproduced on: Windows 11, macOS 15.7.5 (M1 Max)
Not reproduced on: No other environment tested
Notes:
- If popups appear asking to allow MCP Tools, select allow
- The crash might not occur the first time
First few lines of the stack trace:
0x00007FF882B6B51B (Unity) Scripting::UnityEngine::SubsystemManagerProxy::ClearSubsystems
0x00007FF882B6FBE7 (Unity) SubsystemManager::CleanupInstances
0x00007FF882B6F54E (Unity) SubsystemManager::`vector deleting destructor'
0x00007FF88062563F (Unity) RuntimeStatic<SubsystemManager,0>::Destroy
0x00007FF88389CB90 (Unity) RegisterRuntimeInitializeAndCleanup::ExecuteCleanup