What makes the "nuget/nuget.xml" artifact to be generated, or not ?

Hello, 

I am using Teamcity to generate several .Net project, some old ones in .Net 4.7.2, some others in .Net 8.

I would like to have the “nuget packages” tab always generated in my build, I have it on some builds (and the related "nuget/nuget.xml" file in Artifacts), like below :

But on most of my builds the tab doesn't appear. I have tried with “dotnet restore” command, old “nuget restore” command… And I never understand why sometimes the nuget/nuget.xml is present, sometimes (for other build configuration, but very looking like the working ones) I don't have it.

Is there a specific parameter to use to produce the file ? When is it supposed to be generated and by which tool/command please ?

Thank you