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add-cli-command

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Add or change a dotnet CLI command, subcommand, or option across the relevant CLI projects. USE FOR: adding or changing a dotnet CLI command/subcommand, adding a new Option<T> or Argument<T>, registering a subcommand in the command tree, changing an option's help description or a command's runtime message, wiring a command parser, or updating --help output.

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How to use this skill

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Source SKILL.md: https://github.com/dotnet/dotnet/blob/HEAD/src/sdk/.github/skills/add-cli-command/SKILL.md

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

Add or change a dotnet CLI command or option

See references/file-map.md for the exact file map and the two-resx reference table. Read it before editing.

Add an option to an existing command

  1. Declare the option in src/Cli/Microsoft.DotNet.Cli.Definitions/Commands/<Area>/<Name>CommandDefinition.cs. Prefer a CommonOptions factory (Common/CommonOptions.cs) when one exists:

    public readonly Option<bool> NoLogoOption = CommonOptions.CreateNoLogoOption();
// or, declared inline:
public readonly Option<string> OutputOption = new Option<string>("--output", "-o")
{
    Description = CommandDefinitionStrings.BuildOutputOptionDescription
};

    Add it to the command in the constructor: Options.Add(OutputOption);.

  2. Consume it in the managed implementation under src/Cli/dotnet/Commands/<Area>/... via definition.OutputOption; runtime messages come from CliCommandStrings.<Key>.

  3. Strings: add the help description to CommandDefinitionStrings.resx and any runtime message to CliCommandStrings.resx, then regenerate the .xlf siblings.

  4. Test: add parser/validation tests under test/dotnet.Tests/CommandTests/<Area>/ and update any Verify help snapshots.

Add a new command

Everything above, plus:

  1. Create Commands/<Area>/<Name>CommandDefinition.cs in the Definitions project.

  2. Register it in the root tree (Commands/DotNetCommandDefinition.cs constructor):

    Subcommands.Add(<Name>Command = new());

  3. Create the managed implementation and a <Name>CommandParser.cs exposing ConfigureCommand(...) under src/Cli/dotnet/Commands/<Name>/.

  4. Wire the parser in src/Cli/dotnet/Parser.cs ConfigureManagedActions:

    <Name>CommandParser.ConfigureCommand(rootCommand.<Name>Command);

Native AOT: a newly registered command already runs under Native AOT via the managed fallback (the dotnet-aot host runs dotnet.dll through hostfxr), and its parsing and --help reach the AOT CLI for free. Making the command execute in-process in the native binary is separate, deliberate work — follow the add-dotnet-aot-command skill when AOT support is required.

Checklist

  • Option/command declared in Definitions, registered in its parent's constructor.
  • Managed behavior wired in src/Cli/dotnet and (for new commands) in Parser.cs.
  • Help description in CommandDefinitionStrings.resx; runtime message in CliCommandStrings.resx.
  • .xlf files regenerated via /t:UpdateXlf (not hand-edited), resx + xlf committed together.
  • No heavy dependency leaked into Definitions.
  • For in-process AOT execution, followed add-dotnet-aot-command (managed fallback applies otherwise).
  • Tests added/updated; Verify *.verified.txt snapshots promoted if CLI output changed.