Option

A CLI Option is a parameter to your command line application that is called with a single or double dash, something like --verbose or -v.

def Option(
    default: Any | None = ...,
    param_decls: str,
    callback: Callable[..., Any] | None = None,
    metavar: str | None = None,
    expose_value: bool = True,
    is_eager: bool = False,
    envvar: str | list[str] | None = None,
    shell_complete: Callable | None = None,
    autocompletion: Callable[..., Any] | None = None,
    default_factory: Callable[[], Any] | None = None,
    parser: Callable[[str], Any] | None = None,
    click_type: click.ParamType | None = None,
    show_default: bool | str = True,
    prompt: bool | str = False,
    confirmation_prompt: bool = False,
    prompt_required: bool = True,
    hide_input: bool = False,
    is_flag: bool | None = None,
    flag_value: Any | None = None,
    count: bool = False,
    allow_from_autoenv: bool = True,
    help: str | None = None,
    hidden: bool = False,
    show_choices: bool = True,
    show_envvar: bool = True,
    case_sensitive: bool = True,
    min: int | float | None = None,
    max: int | float | None = None,
    clamp: bool = False,
    formats: list[str] | None = None,
    mode: str | None = None,
    encoding: str | None = None,
    errors: str | None = "strict",
    lazy: bool | None = None,
    atomic: bool = False,
    exists: bool = False,
    file_okay: bool = True,
    dir_okay: bool = True,
    writable: bool = False,
    readable: bool = True,
    resolve_path: bool = False,
    allow_dash: bool = False,
    path_type: None | type[str] | type[bytes] = None,
    rich_help_panel: str | None = None
) - > OptionInfo

A CLI Option is a parameter to your command line application that is called with a single or double dash, something like --verbose or -v.

Parameters

Name	Type	Description
default	`Any	None` = ...
param_decls	str	One or multiple aliases (e.g., '--user', '-u') defining how the option is called on the command line.
callback	`Callable[..., Any]	None` = None
metavar	`str	None` = None
expose_value	bool = True	Whether to pass the value to the command callback and store it on the context.
is_eager	bool = False	If True, processes this option before other parameters to handle early-exit logic like version flags.
envvar	`str	list[str]
shell_complete	`Callable	None` = None
autocompletion	`Callable[..., Any]	None` = None
default_factory	`Callable[[], Any]	None` = None
parser	`Callable[[str], Any]	None` = None
click_type	`click.ParamType	None` = None
show_default	`bool	str` = True
prompt	`bool	str` = False
confirmation_prompt	bool = False	Whether to ask the user to type the value twice for confirmation (e.g., for passwords).
prompt_required	bool = True	If False, only prompts if the option flag is provided without an accompanying value.
hide_input	bool = False	Whether to mask user input during a prompt, typically used for sensitive data.
is_flag	`bool	None` = None
flag_value	`Any	None` = None
count	bool = False	Whether to treat the option as a counter that increments with each occurrence (e.g., -vvv).
allow_from_autoenv	bool = True	Whether to allow pulling values from environment variables based on a context prefix.
help	`str	None` = None
hidden	bool = False	Whether to hide this option from the help output entirely.
show_choices	bool = True	Whether to display valid Enum choices inline during an interactive prompt.
show_envvar	bool = True	Whether to display the associated environment variable name in the help text.
case_sensitive	bool = True	Whether Enum choice matching should respect character casing.
min	`int	float
max	`int	float
clamp	bool = False	Whether to force out-of-bounds numeric input to the nearest min/max boundary instead of erroring.
formats	`list[str]	None` = None
mode	`str	None` = None
encoding	`str	None` = None
errors	`str	None` = "strict"
lazy	`bool	None` = None
atomic	bool = False	Whether to perform file writes using a temporary file to ensure atomic updates.
exists	bool = False	Whether to validate that the provided Path exists on the filesystem.
file_okay	bool = True	Whether the Path is allowed to be a file.
dir_okay	bool = True	Whether the Path is allowed to be a directory.
writable	bool = False	Whether to check if the Path is writable by the current user.
readable	bool = True	Whether to check if the Path is readable by the current user.
resolve_path	bool = False	Whether to convert the Path to an absolute path and resolve all symlinks.
allow_dash	bool = False	Whether to allow '-' as a path value to represent stdin/stdout.
path_type	`None	type[str]
rich_help_panel	`str	None` = None

Returns

Type	Description
OptionInfo	An object containing the configuration metadata for a Typer CLI option.