The Spec action creates a nuspec for a package. The nuspec is later used by the Pack action to create the NuGet package.
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NuGet Spec Options
Package Name or Project File
You can specify either a project name or a project file. A project name will cause a new blank spec to be created. If you specify a Project File the nuspec will be based on the project metadata.
Output Directory
The directory where the nuspec file should be created.
Optional Parameters
Assembly
You can optionally specify an assembly from which to get metadata.
Force
This will overwrite the nuspec file if it already exists.