CodeGen creates empty mapper file on the first build - mapster

Question

When I decorate my domain class with [AdaptTo("[name]Dto"), GenerateMapper] everything works fine, but when I use:
public class MappingRegister : ICodeGenerationRegister
{
public void Register(CodeGenerationConfig config)
{
config.AdaptTo("[name]Read")
.ForType<Command>();
config.GenerateMapper("[name]Mapper")
.ForType<Command>();
}
}
it generates the same dto class as with an attribute, but the mapper class is empty:
public static partial class CommandMapper
{
}
What do I miss?
Update
So the issue that I have is not with attribute vs ICodeGenerationRegister implementation, but the fact that I have to run the build twice. The First time it generates an empty mapper class and on the second build, I get the extension methods generated.
Here is my project config
...
<Target Name="Mapster" AfterTargets="AfterBuild">
<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet tool restore" />
<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster model -a "$(TargetDir)$(ProjectName).dll" -n Commands.Dtos -o Dtos" />
<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster extension -a "$(TargetDir)$(ProjectName).dll" -n Commands.Dtos -o Dtos" />
<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster mapper -a "$(TargetDir)$(ProjectName).dll" -n Commands.Dtos -o Dtos" />
</Target>
...
Mapster tool version 8.0.1