The type or namespace name 'UniTask<>' could not be found

Issue

After importing AI Dev Kit into Unity, you encounter a flood of errors saying “The type or namespace name 'UniTask<>' could not be found.” like in the screenshot below.

Possible Cause

In rare cases, Unity fails to automatically apply the required Scripting Define Symbol (UNITY_NEWTONSOFT_JSON, CYSHARP_UNITASK) during installation. This prevents the editor scripts from activating, resulting in the AI Dev Kit menu not appearing.

How to Fix

• Open File > Build Settings > Project Settings > Player > Other Settings

• Locate the Scripting Define Symbols field for your current build target

• Manually add these two symbols:

  UNITY_NEWTONSOFT_JSON
  CYSHARP_UNITASK

• Press Enter or click elsewhere to confirm the change

• Unity should now recompile the scripts, and the AI Dev Kit menu should appear under Tools

If It Still Doesn’t Work

• Sometimes, Unity also fails to automatically install required dependencies during the package import. Make sure you have following folders in Packages in your project window:

  • Newtonsoft Json

  • UniTask

• If you are missing any of the above, manual install the dependencies.

  • Newtonsoft.Json: Manual Installation Guide

  • Cysharp.UniTask: Manual Installation Guide

• Each guide provides step-by-step instructions for adding the packages to your Unity project and verifying that everything is set up correctly. After completing the installations, restart Unity to ensure the changes take effect.

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