import typer app = typer.Typer() @app.command() def main(name: str = typer.Argument(..., help="The name of the user to greet")): print(f"Hello {name}") if __name__ == "__main__": app() And it will be used in the automatic --help option: $ uv run python main.py --help // Check the section with ...

// Call it with CLI parameters $ uv run python main.py Camila --age 15 --height-meters 1.70 --female // All the data has the correct Python type name is Camila, of type: class 'str' --age is 15, of type: class 'int' --height-meters is 1.7, of type: class 'float' --female is True, of type: class ...

Python 3.10+ from pathlib import Path import typer app = typer.Typer() @app.command() def main(files: list[Path], celebration: str): for path in files: if path.is_file(): print(f"This file exists: {path.name}") print(celebration) if __name__ == "__main__": app() And then you can pass it as ...

The same way as with a CLI application with a single command, subcommands (or just "commands") can also have their own CLI arguments: Python 3.10+ import typer app = typer.Typer() @app.command() def create(username: str): print(f"Creating user: {username}") @app.command() def delete(username: str): print(f"Deleting user: {username}") if __name__ == "__main__": app() // Check the help for create $ uv run python main.py create --help Usage: main.py create [OPTIONS] {username} Arguments: username [required] Options: --help Show this message and exit.

import typer from types import SimpleNamespace cli = typer.Typer() @cli.callback() def main( ctx: typer.Context, pinboard_token: str = typer.Option(None, envvar="PINBOARD_TOKEN"), ): if not pinboard_token: print( "Missing pinboard token; pass --pinboard-token or set env[PINBOARD_TOKEN]" ) raise typer.Exit(1) ctx.obj = SimpleNamespace(pinboard_token = pinboard_token) @cli.command() def all(ctx: typer.Context): # do something with ctx.obj.pinboard_token @cli.command() def new(ctx: typer.Context): # do something with ctx.obj.pinboard_token if __name__ == "__main__": cli()

In fact, it's very common to have optional CLI arguments, it's way more common than having required CLI options. As an example of how it could be useful, let's see how the ls CLI program works. // If you just type $ ls // ls will "list" the files and directories in the current directory typer tests README.md LICENSE // But it also receives an optional CLI argument $ ls ./tests/ // And then ls will list the files and directories inside of that directory from the CLI argument __init__.py test_tutorial

**Example** ```python def name_callback(value: str): if value != "Deadpool": raise typer.BadParameter("Only Deadpool is allowed") return value @app.command() def main(name: Annotated[str, typer.Argument(callback=name_callback)]): print(f"Hello {name}") ``` """ ), ] = None, metavar: Annotated[ str | None, Doc( """ Customize the name displayed in the help text to represent this CLI Argument.

import typer from typing import List from pathlib import Path app = typer.Typer(name="demo", add_completion=False, help="This is a demo app.") @app.command() def talk(text: str = typer.Argument(..., help="The text to type."), repeat: int = typer.Option(1, help="Number of times to repeat."), loud: bool = typer.Option(False, is_flag=True)): """Talks some text below""" if loud: text = text.upper() for _ in range(repeat): print(text) if __name__ == "__main__": app() The talk command can be run in multiple ways now. python cli.py talk "hello there" python cli.py talk "hello there" --repeat 2 python cli.py talk "hello there" --loud python cli.py talk "hello there" --loud --repeat 3

July 23, 2025 - ... # Python program to print "Hello World!" # By taking passing argument # value as "World!" in parameter name import typer # Function having parameter name def main(name): print(f"Hello {name}") typer.run(main)

Python 3.10+ - non-Annotated · Tip · Prefer to use the Annotated version if possible. import typer app = typer.Typer() @app.command() def main(user_name: str = typer.Option(..., "--name")): print(f"Hello {user_name}") if __name__ == "__main__": app() Note · "Positional" means that it's not ...

import typer from typing import List from pathlib import Path app = typer.Typer(name="demo", add_completion=False, help="This is a demo app.") @app.command() def hello_world(name): """Say hello""" print(f"hello {name}!") @app.command() def goodbye_world(name): """Say goodbye""" print(f"goodbye {name}!") @app.command() def add(n1: int = typer.Argument(..., help="An integer"), n2: int = typer.Argument(1, help="An integer")): """Add two numbers""" print(n1 + n2) if __name__ == "__main__": app() By adding the argument information we should now see a help text appear for each input but we should now also see proper addition taking place instead of string concatenation. python cli.py add --help python cli.py add 1 1 ·

August 11, 2025 - import typer def greet(name: str = typer.Argument("World")): typer.echo(f"Hello, {name}!") if __name__ == "__main__": typer.run(greet) ... # With argument $ python app.py John Hello, John!

And we pass it as the first function argument to typer.Argument(). ... The word "factory" in default_factory is just a fancy way of saying "function that will create the default value". ... // Check the help $ uv run python main.py --help Usage: main.py [OPTIONS] [name] Arguments: name [default: (dynamic)] Options: --help Show this message and exit.

April 28, 2023 - Lets see an example - import typer app = typer.Typer() @app.command() def hello_world(): print("hello world") @app.command() def hello(name): print(f"hello {name}") if __name__ == "__main__": app()

│</font> <font color="#A5A5A1">╰─────────────────────────────────────────────────────────────────╯</font> // There are now 2 CLI arguments, name and lastname // Now pass a single name argument $ uv run python main.py Camila <font color="#F4BF75">Usage: </font>main.py [OPTIONS] {name} {lastname} <font color="#A5A5A1">Try </font><font color="#44919F">&apos;main.py </font><font color="#44919F"><b>--help</b></font><font color="#44919F">&apos;</font><font color="#A

│ ╰───────────────────────────────────────────────────╯ // Now pass the 'name' argument $ uv run python main.py Camila Hello Camila // It works! 🎉 · Note: you can also call this same script with the typer command, but you don't need to. This was the simplest example possible.

│ ╰───────────────────────────────────────────────────╯ // Now pass the 'name' argument $ uv run python main.py Camila Hello Camila // It works! 🎉 · Note: you can also call this same script with the typer command, but you don't need to. This was the simplest example possible.

June 5, 2023 - from typing import Optional import typer def main(name: str, age: Optional[int] = None): message = f"Hello {name}" if age is not None: message = f"{message}, age {age}" print(message) if __name__ == "__main__": typer.run(main) You can run both of these with python app.py NAME --age AGE.

June 5, 2025 - import time from typing import Optional import typer from rich import print, progress, prompt app = typer.Typer() # Callback definition: https://typer.tiangolo.com/tutorial/commands/callback/ @app.callback(help="App callback definition") def callback( arg1: str = typer.Argument(..., help="Required argument for the entire app"), option1: bool = typer.Option(default=False, help="Optional argument for the entire app"), ) -> None: print(f"{arg1=}") print(f"{option1=}") # Required arguments: https://typer.tiangolo.com/tutorial/commands/arguments/…