There is an ambiguous pronoun (it) in your question, so I will answer both cases.
Is it possible to manually add a third party nupkg file to a Nuget feed? Yes. Just send the package to the feed. Either through nuget.org, or if it is a private channel, to the URL of the private channel. I assume that if so, you should use a private feed. TeamCity also has an internal NuGet channel that can be published directly. Read more: How to add a custom nuget channel to a TeamCity assembly?
Is it possible to manually add a third-party nupkg file directly to TeamCity No. You will need to go through the NuGet feed. However, nuget.exe supprots sets up a local repository, but is not sure if Team City supports this syntax.
After all this, it may be easier for you to simply check your nuget directroy source packages so that you donβt have to worry about restoring packages on your build server. This way you don't have to bother with this, just add your third-party nupkg files to the packages directory in your solution.
UPDATE: As an alternative to adding your packages to the original control, you can configure your NuGet personal channel and localhost or purchase it using the MyGet tool. You can then configure your feed as the source of the nuget package in TeamCity.
Philip pittle
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