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fastapi/typer

📈 Trending★ 19,432PythonAudience · developerComplexity · 2/5ActiveLicenseSetup · easy

TLDR

Python library that turns functions into command-line tools automatically using type hints, eliminating boilerplate for CLI argument handling and help text.

Mindmap

mindmap
  root((repo))
    What it does
      Auto-generates CLIs
      Reads type hints
      Handles arguments
      Generates help text
    How it works
      Built on Click
      Uses Rich output
      Decorates functions
      Parses signatures
    Use cases
      Simple scripts
      Multi-command tools
      Team utilities
      Package CLIs
    Tech stack
      Python 3
      Type hints
      Click
      Rich

Things people build with this

USE CASE 1

Build a deployment tool that accepts environment flags and validates inputs automatically.

USE CASE 2

Create a multi-command CLI for managing database migrations with subcommands and help text.

USE CASE 3

Turn a Python script into a user-friendly tool your team can run without reading code.

USE CASE 4

Package a Python utility with auto-completion and formatted terminal output.

Tech stack

PythonClickRichType hints

Getting it running

Difficulty · easy Time to first run · 5min
MIT license, use freely for any purpose, including commercial, as long as you keep the copyright notice.

In plain English

Typer is a Python library for building command-line interface (CLI) tools, programs that run in a terminal and accept commands and options like "myapp deploy --env production". The problem it solves is that writing CLI tools in Python has traditionally required a lot of boilerplate: you have to manually define arguments, write help text, handle errors, and set up tab-completion. Typer makes this nearly effortless by reading your standard Python function signatures and type annotations to figure out all of that automatically. For example, a plain Python function that takes a "name" argument becomes a CLI command with proper help text, error messages for missing arguments, and shell auto-completion, with almost no extra code. You can build simple single-command tools or complex multi-command CLIs with subcommands by just decorating functions. Typer also ships with a "typer" command-line tool that can run any plain Python script as a CLI app even if it does not use Typer directly. It is built on top of Click (a popular Python CLI library) and integrates with the Rich library for colorful, well-formatted terminal output. You would use Typer whenever you want to turn a Python script into a user-friendly command-line tool for yourself, your team, or as part of a Python package. The stack is Python 3 with type hints.

Copy-paste prompts

Prompt 1
Show me how to create a Typer CLI that takes a name argument and prints a greeting with proper help text.
Prompt 2
How do I add subcommands to a Typer app so users can run 'myapp deploy' and 'myapp status'?
Prompt 3
Create a Typer command that accepts optional flags like --verbose and --output-file with type validation.
Prompt 4
How do I integrate Rich formatting into Typer to display colored output and tables in my CLI?
Prompt 5
Show me how to add shell tab-completion to a Typer CLI app.
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.