Flags (named options)

Parameters without [Argument] become --kebab-case long flags. A bool flag defaults to false; pass --flag to set it.

public static Task<int> Build(string outputDir, bool release = false) { … }
// myapp build --output-dir ./bin --release
		

C# parameter names are automatically converted from camelCase to kebab-case:

• outputDir → --output-dir
• dryRun → --dry-run
• verbose → --verbose

By default the CLI long name is derived from the C# parameter name. To use a different primary name, place a --long-name token before the description in an XML <param> tag.

Additional --names after the first become aliases. Once an explicit long name is specified, the derived name is dropped entirely.

/// <summary>Tag one or more resources.</summary>
/// <param name="tags">-t, --tag, Tags to apply.</param>
public static void Tag(string[] tags) { … }
		

--tag a --tag b    ✓  (explicit primary name)
-t a               ✓  (short alias)
--tags             ✗  (derived name is dropped)
		

/// <param name="outputDir">-o, --out, --output, Output directory.</param>
public static void Build(string outputDir) { … }
		

--out ./bin         ✓  (primary)
--output ./bin      ✓  (alias)
-o ./bin            ✓  (short alias)
--output-dir        ✗  (derived name is dropped)
		

A bool? flag generates both --flag (sets true) and --no-flag (sets false). Omitting either leaves the value null, letting you distinguish "not specified" from an explicit false.

Help output shows --flag / --no-flag for nullable bools.

public static Task<int> Deploy(string env, bool? dryRun = null) { … }
// myapp deploy staging               → dryRun is null
// myapp deploy staging --dry-run     → dryRun is true
// myapp deploy staging --no-dry-run  → dryRun is false
		

Parameters without a default value are required flags. Parameters with a default value are optional.

public static Task<int> Deploy(
    string environment,
    bool dryRun = false,
    string? region = null)
{ … }
		

1. required: --environment <value>
2. optional: --dry-run
3. optional: --region <value>

Collection flags (T[], List<T>) accept the flag multiple times by default. Use [CollectionSyntax] for comma-separated values instead.

public static Task<int> Deploy(string[] targets, [CollectionSyntax(Separator = ",")] string[] tags) { … }
// Repeated:   myapp deploy --targets web --targets api
// Separator:  myapp deploy --targets web,api --tags blue,green