Typer CLI
Typer CLI runs Python scripts with arguments, help and type validation even when the script does not import Typer itself.
- 20,292 ★ on the repository
- Last commit
- MIT
Extended access
Why this level
- The command executes Python scripts and imports with current-process permissions.
Install
In your terminal, with SkillFoxx CLI
npx skillfoxx add cli/typer-cliDetects the agents on your machine, shows the access level and pins the version.
Other ways to install
Access and checks
How we reviewExtended accessThe tool runs code or makes network calls and only reads external data.
- The command executes Python scripts and imports with current-process permissions.
This is third-party code. Review the repository files before installing.
What it does
Typer reads a Python function signature and builds a command-line interface: parameter names become arguments and annotations define expected types. If a required argument is missing, the error names it and shows how to open help. The function body can stay unchanged. The CLI suits an existing utility script. For an application with several operations, the author creates `typer.Typer()` and marks functions with `@app.command()`. Help then lists separate subcommands with their own arguments, which can be invoked through Python.
Who it is for. Authors of small Python scripts needing clear arguments and help without separate CLI boilerplate.
Good fit when
- A colleague runs a utility script but cannot remember its arguments.
- A finished Python function needs a command-line interface.
- Numbers and paths arrive from a shell where input-type mistakes are common.
- Several utility operations have grown into an application with subcommands.
Not a fit when
- The selected Python script may not be executed.
- Type hints must prove business-logic correctness.
- You need a finished task tool without supplying a script.
Example request
Show Typer CLI help for my reviewed main.py and explain arguments without executing production work.Limitations
The first installation adds Typer through uv to a project; its executable lives in that project’s `.venv`, not a global environment. Direct `typer` calls and shell completion require that environment to be active in the current terminal. The interface follows function signatures and annotations: input validation does not prove application logic correct. The script and its imports run with process permissions, so even requesting help should be limited to trusted code.
How to disable. Stop the script and remove the project dependency if needed. Its command belongs to that environment.
FAQ
How do I pass an argument to an ordinary function?
The README’s `main(name: str)` function in `main.py` prints a greeting. `typer main.py run Camila` passes the name and prints `Hello Camila`.
How do I inspect example arguments?
Use `typer main.py run --help` with a reviewed file.
The command is missing after `uv add typer`?
It is installed in the project’s `.venv`. On Linux or macOS, run `source .venv/bin/activate` from the project directory, then retry `typer`. Other shells have their own activation command in the official installation guide.
Where do argument types come from?
From function annotations: for example, a string parameter becomes a string argument. Help describes expected input.
How do I invoke the same example through Python?
Add `import typer` and call `typer.run(main)` under `if __name__ == "__main__"`. Then `uv run python main.py Camila` prints the same greeting.
Discussion
No questions or reviews yet.
Related
CLI toolstypos is a spelling-check CLI with a preview diff, so users can review project names before writing corrections.
Textual CLI serves an existing terminal application in a browser, letting its author show the same Python code on the web.
Methods for an agent in one CLI: comparing options, solving problems and changing code in steps, 20 slash commands in all.
The CLI runs TypeScript files in Node.js without a separate build step for agent-prepared scripts and local utilities.
A zero-config linter and formatter for JavaScript and TypeScript, with ready presets for dozens of AI agents and editors
The CLI validates OpenAPI descriptions and generates client libraries, MCP servers and other interfaces for your API.
README in short
Subcommands have their own help: in the expanded example, `uv run python main.py hello --help` displays arguments for `hello` alone.