You can re-download your project from https://aspnetzero.com/Download, then copy "aspnet-core\AspNetZeroRadTool" folder.
Copy "aspnet-core\AspNetZeroRadTool" folder to your project.
What is you project version?
Tool works with v5.0.0+ projects.
You can delete one of them and use the other one as common.
does "aspnet-core\AspNetZeroRadTool\config.json" file exist in your project folder?
We've just released v1.5.7.1 to fix this issue once again.
See the reason of the change in v1.5.7 : https://support.aspnetzero.com/QA/Questions/5570
see <a class="postlink" href="https://aspnetzero.com/Documents/Development-Guide-Rad-Tool">https://aspnetzero.com/Documents/Develo ... e-Rad-Tool</a> There is not a list of placeholders but you can find them in templates.
I think the best solution is to use the same ones in common.
see <a class="postlink" href="https://github.com/aspnetzero/aspnet-zero-core/issues/1049#issuecomment-381206936">https://github.com/aspnetzero/aspnet-ze ... -381206936</a>
Do you get the same error when you run "add-migration" command on package manager console or command line?