Command Attributes Reference

This page lists every attribute you can set on the #[command] attribute at the top level.

Top-level attributes

Key	Type	Default	Description
help	string	From doc comment or empty	Short description shown in command listings and per-command help
details	string	From doc comment or empty	Long description shown only in --help output
name	string	Function name	Override the CLI command name
aliases	array of strings	Empty	Alternative names that resolve to this command
hidden	bool	false	Omit from app-level help listing; command remains invocable
deprecated	bool	false	Emit a deprecation warning when the command is invoked
deprecation_note	string	Empty	Supplementary message appended to the deprecation warning

Attribute types

String attributes

String attributes must be string literals:

#[command(
    help = "Deploy the application",
    details = "Long description here.",
    name = "ship",
    deprecation_note = "use 'upload' instead",
)]
fn deploy(...) { ... }

Boolean attributes

Boolean attributes must be true or false literals:

#[command(
    hidden = true,
    deprecated = false,
)]
fn debug(...) { ... }

Array attributes

Array attributes must be arrays of string literals:

#[command(aliases = ["ship", "release", "push"])]
fn deploy(...) { ... }

Doc comment priority

If you provide both a doc comment and an explicit help or details attribute, the explicit attribute takes priority:

#[command(help = "Explicit help wins")]
/// This doc comment help is ignored
fn deploy(...) { ... }

Doc comment splitting

A blank line in a doc comment separates help from details:

#[command]
/// Short help text
///
/// Long details text shown only on --help.
/// Can span multiple paragraphs.
fn deploy(...) { ... }

This is equivalent to:

#[command(
    help = "Short help text",
    details = "Long details text shown only on --help.\nCan span multiple paragraphs.",
)]
fn deploy(...) { ... }

Behavior notes

Deprecated commands

• Render with the deprecated style (dim by default) in the app-level command listing
• Display a "warning: this command is deprecated" banner in per-command help output
• Print a warning to stderr at runtime before executing

Aliased commands

• Invocable by any registered alias
• Primary command name is always shown in help listings
• Aliases do not appear in the listing

Hidden commands

• Omitted from the command listing
• Remain fully invocable
• Useful for debug or migration commands

Oneshot mode restrictions

When using app!(cmd), the following attributes on the command are forbidden and cause a panic at startup:

Forbidden attribute	Panic message
aliases	"oneshot command must not have aliases"
name (custom)	"oneshot command must not have a custom name"
hidden = true	"oneshot command must not be hidden"
deprecated = true	"oneshot command must not be deprecated"

Additionally, if more than one #[command] is registered in the binary, app!(cmd) panics with "oneshot mode requires exactly one command".