.NET Core Global Tools overview
This article applies to: ✓ .NET Core 2.1 SDK
A .NET Core Global Tool is a special NuGet package that contains a console application. A Global Tool can be installed on your machine on a default location that is included in the PATH environment variable or on a custom location.
If you want to use a .NET Core Global Tool:
- Find information about the tool (usually a website or GitHub page).
- Check the author and statistics in the home for the feed (usually NuGet.org).
- Install the tool.
- Call the tool.
- Update the tool.
- Uninstall the tool.
.NET Core Global Tools appear on your path and run in full trust. Do not install .NET Core Global Tools unless you trust the author.
Find a .NET Core Global Tool
Currently, there isn't a Global Tool search feature in the .NET Core Command-line Interface (CLI).
You can find .NET Core Global Tools on NuGet. However, NuGet doesn't yet allow you to search specifically for .NET Core Global Tools.
You may also find tool recommendations in blog posts or in the natemcmaster/dotnet-tools GitHub repository.
You can also see the source code for the Global Tools created by the ASP.NET team at the aspnet/DotNetTools GitHub repository.
Check the author and statistics
Since .NET Core Global Tools run in full trust and are generally installed on your path, they can be very powerful. Don't download tools from people you don't trust.
If the tool is hosted on NuGet, you can check the author and statistics by searching for the tool.
Install a Global Tool
To install a Global Tool, you use the dotnet tool install .NET Core CLI command. The following example shows how to install a Global Tool in the default location:
dotnet tool install -g dotnetsay
If the tool can't be installed, error messages are displayed. Check that the feeds you expected are being checked.
If you're trying to install a pre-release version or a specific version of the tool, you can specify the version number using the following format:
dotnet tool install -g <package-name> --version <version-number>
If installation is successful, a message is displayed showing the command used to call the tool and the version installed, similar to the following example:
You can invoke the tool using the following command: dotnetsay Tool 'dotnetsay' (version '2.0.0') was successfully installed.
Global Tools can be installed in the default directory or in a specific location. The default directories are:
These locations are added to the user's path when the SDK is first run, so Global Tools installed there can be called directly.
Note that the Global Tools are user-specific, not machine global. Being user-specific means you cannot install a Global Tool that is available to all users of the machine. The tool is only available for each user profile where the tool was installed.
Global Tools can also be installed in a specific directory. When installed in a specific directory, the user must ensure the command is available, by including that directory in the path, by calling the command with the directory specified, or calling the tool from within the specified directory. In this case, the .NET Core CLI doesn't add this location automatically to the PATH environment variable.
Use the tool
Once the tool is installed, you can call it by using its command. Note that the command may not be the same as the package name.
If the command is
dotnetsay, you call it with:
If the tool author wanted the tool to appear in the context of the
dotnet prompt, they may have written it in a way that you call it as
dotnet <command>, such as:
You can find which tools are included in an installed Global Tool package by listing the installed packages using the dotnet tool list command.
You can also look for usage instructions at the tool's website or by typing one of the following commands:
<command> --help dotnet <command> --help
What could go wrong
Global Tools are framework-dependent applications, which means they rely on a .NET Core runtime installed on your machine. If the expected runtime is not found, they follow normal .NET Core runtime roll-forward rules such as:
- An application rolls forward to the highest patch release of the specified major and minor version.
- If there is no matching runtime with a matching major and minor version number, the next higher minor version is used.
- Roll forward doesn't occur between preview versions of the runtime or between preview versions and release versions. Thus, Global Tools created using preview versions must be rebuilt and republished by the author and reinstalled.
- Additional issues can occur with Global Tools created in .NET Core 2.1 Preview 1. For more information, see .NET Core 2.1 Preview 2 Known Issues.
If an application cannot find an appropriate runtime, it fails to run and reports an error.
Another issue that might happen is that a Global Tool that was created during an earlier preview may not run with your currently installed .NET Core runtimes. You can see which runtimes are installed on your machine using the following command:
Contact the author of the Global Tool and see if they can recompile and republish their tool package to NuGet with an updated version number. Once they have updated the package on NuGet, you can update your copy.
The .NET Core CLI tries to add the default locations to the PATH environment variable on its first usage. However, there are a couple of scenarios where the location might not be added to PATH automatically, such as:
- If you've set the
- On macOS, if you've installed the .NET Core SDK using .tar.gz files and not .pkg.
- On Linux, you need to edit the shell environment file to configure the PATH.
Other CLI commands
The .NET Core SDK contains other commands that support .NET Core Global Tools. Use any of the
dotnet tool commands with one of the following options:
-gspecifies that the command is applicable to user-wide Global Tools.
--tool-pathspecifies a custom location for Global Tools.
To find out which commands are available for Global Tools:
dotnet tool --help
Updating a Global Tool involves uninstalling and reinstalling it with the latest stable version. To update a Global Tool, use the dotnet tool update command:
dotnet tool update -g <packagename>
Remove a Global Tool using the dotnet tool uninstall:
dotnet tool uninstall -g <packagename>
To display all of the Global Tools currently installed on the machine, along with their version and commands, use the dotnet tool list command:
dotnet tool list -g