# fastapi/typer

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18,871 stars · 847 forks · Python · mit

## Links

- GitHub: https://github.com/fastapi/typer
- Homepage: https://typer.tiangolo.com/
- awesome-repositories: https://awesome-repositories.com/repository/fastapi-typer.md

## Topics

`cli` `click` `python` `python3` `shell` `terminal` `typehints` `typer`

## Description

This project is a Python framework for building command-line interfaces by converting standard functions into executable programs. It uses type hints to automatically infer and generate argument parsers, validation logic, and help documentation, allowing developers to define complex terminal applications through simple function signatures.

The framework distinguishes itself through a decorator-driven registration system that enables the construction of hierarchical command trees. It supports dependency injection to manage shared state and runtime configuration across subcommands, and it utilizes reflective metadata inspection to dynamically build help screens and parameter configurations.

Beyond core parsing, the library provides a comprehensive suite of tools for terminal interaction, including support for interactive prompts, secure input collection, and visual feedback like progress indicators. It also handles advanced system integration tasks such as generating shell completion scripts, reading configuration from environment variables, and formatting terminal output with custom styling.

The project is designed to be installed as a standard Python package, enabling developers to expose command-line entry points directly from their modules.

## Tags

### Development Tools & Productivity

- [CLI Frameworks](https://awesome-repositories.com/f/development-tools-productivity/cli-frameworks.md) — Provides a library for building command-line interfaces by converting standard functions into executable programs using type hints.
- [Command Line Interfaces](https://awesome-repositories.com/f/development-tools-productivity/command-line-interfaces.md) — Converts standard Python functions into executable command-line programs by inferring arguments and help documentation from type hints. ([source](https://typer.tiangolo.com/tutorial/commands/options/))
- [CLI Command Frameworks](https://awesome-repositories.com/f/development-tools-productivity/cli-command-frameworks.md) — Provides a decorator-driven system to register functions as hierarchical subcommands within a command-line interface. ([source](https://typer.tiangolo.com/reference/typer/))
- [Help Text Generators](https://awesome-repositories.com/f/development-tools-productivity/help-text-generators.md) — Automatically generates and displays help documentation for commands and subcommands based on function signatures. ([source](https://typer.tiangolo.com/features/))
- [CLI Command Registrars](https://awesome-repositories.com/f/development-tools-productivity/cli-command-frameworks/cli-command-registrars.md) — Registers functions as executable commands or subcommands to automatically generate help and handle execution. ([source](https://typer.tiangolo.com/tutorial/commands/one-or-multiple/))
- [Function-to-CLI Converters](https://awesome-repositories.com/f/development-tools-productivity/cli-command-frameworks/function-to-cli-converters.md) — Transforms standard functions into executable command-line applications that run directly from the terminal. ([source](https://typer.tiangolo.com/reference/run_launch/))
- [Nested Command Structures](https://awesome-repositories.com/f/development-tools-productivity/cli-command-frameworks/nested-command-structures.md) — Organizes related functions into a single command-line application with nested subcommands and automatic help generation. ([source](https://typer.tiangolo.com))
- [Argument Parsers](https://awesome-repositories.com/f/development-tools-productivity/argument-parsers.md) — Maps function parameters to command-line arguments and options, supporting complex types and environment variables. ([source](https://typer.tiangolo.com/tutorial/multiple-values/arguments-with-multiple-values/))
- [Command Argument Parsers](https://awesome-repositories.com/f/development-tools-productivity/command-argument-parsers.md) — Enables the definition of positional parameters for commands to accept required inputs directly from the terminal. ([source](https://typer.tiangolo.com/tutorial/commands/arguments/))
- [CLI Argument Definitions](https://awesome-repositories.com/f/development-tools-productivity/command-argument-parsers/cli-argument-definitions.md) — Configures command-line arguments with default values to ensure applications function correctly when inputs are omitted. ([source](https://typer.tiangolo.com/tutorial/arguments/default/))
- [Command Hierarchies](https://awesome-repositories.com/f/development-tools-productivity/command-hierarchies.md) — Structures application logic into complex, nested command trees with multiple levels of subcommands. ([source](https://typer.tiangolo.com/tutorial/subcommands/nested-subcommands/))
- [Command-Line Argument Parsers](https://awesome-repositories.com/f/development-tools-productivity/command-line-argument-parsers.md) — Configures positional inputs to allow users to pass required or optional data to the program. ([source](https://typer.tiangolo.com/tutorial/arguments/))
- [Command Line Configuration](https://awesome-repositories.com/f/development-tools-productivity/command-line-configuration.md) — Configures optional parameters with default values, help text, and validation rules for command-line interfaces. ([source](https://typer.tiangolo.com/tutorial/options/))
- [Multi-Value Option Parsers](https://awesome-repositories.com/f/development-tools-productivity/command-options/multi-value-option-parsers.md) — Collect multiple occurrences of a command-line option into a list and convert each value to the required data type. ([source](https://typer.tiangolo.com/tutorial/multiple-values/multiple-options/))
- [Help Generators](https://awesome-repositories.com/f/development-tools-productivity/help-generators.md) — Automatically generates and displays formatted help documentation for commands and subcommands based on function signatures. ([source](https://typer.tiangolo.com/reference/context/))
- [Shell Completion](https://awesome-repositories.com/f/development-tools-productivity/shell-completion.md) — Installs shell-specific scripts to enable interactive command suggestions and parameter discovery. ([source](https://typer.tiangolo.com/tutorial/typer-command/))
- [Shell Completion Generators](https://awesome-repositories.com/f/development-tools-productivity/shell-completion-generators.md) — Generates shell-specific completion scripts to enable tab-based discovery of commands and options in the terminal. ([source](https://typer.tiangolo.com))
- [Command Line Documentation](https://awesome-repositories.com/f/development-tools-productivity/command-line-documentation.md) — Generates automated help documentation for programs and individual commands by parsing docstrings and configuration parameters. ([source](https://typer.tiangolo.com/tutorial/commands/help/))
- [Modular Command Structures](https://awesome-repositories.com/f/development-tools-productivity/command-line-frameworks/modular-command-structures.md) — Supports grouping related command-line operations into separate files and modules for improved project scalability. ([source](https://typer.tiangolo.com/tutorial/one-file-per-command/))
- [CLI Option Mappers](https://awesome-repositories.com/f/development-tools-productivity/command-options/cli-option-mappers.md) — Maps function parameters to optional command-line flags or key-value pairs. ([source](https://typer.tiangolo.com/tutorial/first-steps/))
- [Named Option Definitions](https://awesome-repositories.com/f/development-tools-productivity/command-options/named-option-definitions.md) — Accepts values or flags passed to a command-line application using single or double dash prefixes. ([source](https://typer.tiangolo.com/reference/parameters/))
- [Custom Completion Providers](https://awesome-repositories.com/f/development-tools-productivity/custom-completion-providers.md) — Allows developers to define custom functions that provide dynamic tab-completion suggestions for command-line arguments. ([source](https://typer.tiangolo.com/tutorial/options-autocompletion/))
- [Execution Context Management](https://awesome-repositories.com/f/development-tools-productivity/execution-context-management.md) — Manages and injects runtime state and configuration into commands to facilitate shared data across subcommands. ([source](https://typer.tiangolo.com/reference/context/))
- [Positional Argument Handlers](https://awesome-repositories.com/f/development-tools-productivity/positional-argument-handlers.md) — Accepts required or optional values passed directly as positional parameters to a command-line application. ([source](https://typer.tiangolo.com/reference/parameters/))
- [Progress Indicators](https://awesome-repositories.com/f/development-tools-productivity/progress-indicators.md) — Renders visual progress bars or spinners in the terminal to provide feedback during long-running operations. ([source](https://typer.tiangolo.com/tutorial/progressbar/))
- [Programmatic Command Invokers](https://awesome-repositories.com/f/development-tools-productivity/cli-command-extensions/programmatic-command-invokers.md) — Allows manual execution of command functions and subcommands within application logic, handling argument forwarding and defaults automatically. ([source](https://typer.tiangolo.com/reference/context/))
- [Command Callbacks](https://awesome-repositories.com/f/development-tools-productivity/cli-command-frameworks/command-callbacks.md) — Executes setup logic or shared behavior automatically whenever a command or subcommand group is invoked. ([source](https://typer.tiangolo.com/tutorial/subcommands/callback-override/))
- [Modular Subcommand Integrators](https://awesome-repositories.com/f/development-tools-productivity/code-organization/modular-subcommand-integrators.md) — Integrates separate command groups into a single application structure to maintain clean code separation. ([source](https://typer.tiangolo.com/reference/typer/))
- [Environment Variable Configuration](https://awesome-repositories.com/f/development-tools-productivity/command-argument-parsers/environment-variable-configuration.md) — Reads command-line argument values from environment variables when no explicit input is provided. ([source](https://typer.tiangolo.com/tutorial/arguments/envvar/))
- [Variable Argument Collectors](https://awesome-repositories.com/f/development-tools-productivity/command-argument-parsers/variable-argument-collectors.md) — Allows users to pass a variable number of items for a single command argument. ([source](https://typer.tiangolo.com/tutorial/multiple-values/arguments-with-multiple-values/))
- [Command-Line Autocompletion](https://awesome-repositories.com/f/development-tools-productivity/command-line-autocompletion.md) — Generates shell scripts to provide command suggestions and improve developer efficiency. ([source](https://typer.tiangolo.com/tutorial/first-steps/))
- [Mandatory Parameter Enforcement](https://awesome-repositories.com/f/development-tools-productivity/command-options/mandatory-parameter-enforcement.md) — Enforces mandatory command-line options by omitting default values, ensuring required inputs are provided. ([source](https://typer.tiangolo.com/tutorial/options/required/))
- [Boolean Flag Generators](https://awesome-repositories.com/f/development-tools-productivity/flag-definitions/boolean-flag-generators.md) — Creates boolean command-line options that automatically generate both positive and negative flag variants. ([source](https://typer.tiangolo.com/tutorial/parameter-types/bool/))
- [Interactive Prompts](https://awesome-repositories.com/f/development-tools-productivity/human-in-the-loop-interfaces/interactive-prompts.md) — Requests information from users during command execution by displaying prompts and capturing responses. ([source](https://typer.tiangolo.com/tutorial/prompt/))
- [Context-Aware Autocompletion Providers](https://awesome-repositories.com/f/development-tools-productivity/shell-autocompletion-providers/context-aware-autocompletion-providers.md) — Injects current execution state into autocompletion functions to provide dynamic, context-aware suggestions. ([source](https://typer.tiangolo.com/tutorial/options-autocompletion/))
- [Shell Completion Integrations](https://awesome-repositories.com/f/development-tools-productivity/shell-completion-integrations.md) — Generates and installs shell completion scripts to assist users with command and argument discovery.
- [Validation Logic](https://awesome-repositories.com/f/development-tools-productivity/validation-logic.md) — Executes custom validation logic on input values during parsing to enforce constraints before application execution. ([source](https://typer.tiangolo.com/tutorial/options/callback-and-context/))
- [CLI File Input Handlers](https://awesome-repositories.com/f/development-tools-productivity/cli-file-input-handlers.md) — Enables command-line arguments to be automatically parsed and opened as accessible file objects. ([source](https://typer.tiangolo.com/reference/file_objects/))
- [Autocompletion Contexts](https://awesome-repositories.com/f/development-tools-productivity/cli-tooling/server-to-cli-integrations/autocompletion-contexts.md) — Provides access to the current execution state during shell autocompletion to enable dynamic, context-aware command suggestions. ([source](https://typer.tiangolo.com/tutorial/options-autocompletion/))
- [Empty Input Help Displays](https://awesome-repositories.com/f/development-tools-productivity/command-line-display-tools/empty-input-help-displays.md) — Configures the command-line interface to automatically show usage instructions when the program is executed without any arguments. ([source](https://typer.tiangolo.com/tutorial/commands/))
- [CLI Option Name Customizers](https://awesome-repositories.com/f/development-tools-productivity/command-options/cli-option-name-customizers.md) — Allows customization of command-line flags by specifying explicit long or short names. ([source](https://typer.tiangolo.com/tutorial/options/name/))
- [Execution Context Injectors](https://awesome-repositories.com/f/development-tools-productivity/execution-context-management/execution-context-injectors.md) — Injects runtime metadata into functions to handle conditional logic and shell completion scenarios. ([source](https://typer.tiangolo.com/tutorial/options/callback-and-context/))
- [Exit Status Signaling](https://awesome-repositories.com/f/development-tools-productivity/exit-status-reporters/exit-status-signaling.md) — Signals task success or failure to the calling environment using standard system exit codes. ([source](https://typer.tiangolo.com/tutorial/terminating/))
- [Modular Architecture](https://awesome-repositories.com/f/development-tools-productivity/modular-architecture.md) — Organizes large-scale command-line applications into hierarchical subcommands and separate modules for better maintainability.
- [Path Validation Services](https://awesome-repositories.com/f/development-tools-productivity/path-validation-services.md) — Validates file system paths provided as arguments and converts them into standard path objects. ([source](https://typer.tiangolo.com/tutorial/parameter-types/path/))
- [CLI Scripts](https://awesome-repositories.com/f/development-tools-productivity/terminal-shell-cli/cli-tooling-frameworks/cli-scripts.md) — Enables running scripts as command-line applications with automatic tab completion without formal installation. ([source](https://typer.tiangolo.com/tutorial/typer-command/))
- [Command Suggestion Tools](https://awesome-repositories.com/f/development-tools-productivity/terminal-shell-cli/cli-tooling-frameworks/command-suggestion-tools.md) — Detects mistyped commands and suggests the closest valid matches to assist users with input errors. ([source](https://typer.tiangolo.com/tutorial/commands/help/))

### User Interface & Experience

- [Command-Line Interface Development](https://awesome-repositories.com/f/user-interface-experience/ui-architecture/command-line-interface-development.md) — Converts standard functions into robust terminal applications with automatic argument parsing and help documentation.
- [CLI Input Collectors](https://awesome-repositories.com/f/user-interface-experience/value-decorators/cli-input-collectors.md) — Gather several values for a single command-line argument by allowing users to repeat flags or provide lists of inputs. ([source](https://typer.tiangolo.com/tutorial/multiple-values/))
- [Sensitive Input Prompts](https://awesome-repositories.com/f/user-interface-experience/masked-inputs/sensitive-input-prompts.md) — Collects sensitive user input interactively via the terminal while masking characters on screen. ([source](https://typer.tiangolo.com/tutorial/options/password/))
- [Input Validation Rules](https://awesome-repositories.com/f/user-interface-experience/form-and-input-management/form-validation/input-validation-rules.md) — Applies declarative validation rules to command-line arguments and options to ensure data integrity. ([source](https://typer.tiangolo.com/tutorial/arguments/other-uses/))
- [Input Validation Utilities](https://awesome-repositories.com/f/user-interface-experience/input-validation-utilities.md) — Ensures data integrity in terminal tools by automatically parsing, validating, and converting user inputs into native programming types.
- [Terminal Output Formatters](https://awesome-repositories.com/f/user-interface-experience/terminal-user-interfaces/rendering-output-engines/terminal-output-formatters.md) — Structures and formats multi-line terminal content to improve readability through spacing and layout adjustments. ([source](https://typer.tiangolo.com/tutorial/printing/))
- [User Confirmation Dialogs](https://awesome-repositories.com/f/user-interface-experience/user-confirmation-dialogs.md) — Provides interactive prompts to request user confirmation before proceeding with sensitive or destructive operations. ([source](https://typer.tiangolo.com/tutorial/prompt/))

### Programming Languages & Runtimes

- [Program Entry Points](https://awesome-repositories.com/f/programming-languages-runtimes/program-entry-points.md) — Registers functions as executable command-line programs for direct terminal invocation. ([source](https://typer.tiangolo.com/tutorial/package/))
- [Shared Instance States](https://awesome-repositories.com/f/programming-languages-runtimes/instance-attribute-management/shared-instance-states.md) — Provides dependency injection mechanisms to share state and configuration objects across command hierarchies. ([source](https://typer.tiangolo.com/reference/context/))

### Data & Databases

- [CLI Type Converters](https://awesome-repositories.com/f/data-databases/custom-type-converters/cli-type-converters.md) — Parses and validates command-line arguments into native types based on function hints. ([source](https://typer.tiangolo.com/tutorial/parameter-types/))
- [Type-Safe Request Validators](https://awesome-repositories.com/f/data-databases/data-governance-modeling/data-management-governance/data-integrity-validation/data-validation/type-safe-request-validators.md) — Automatically validates that command-line arguments match expected data types like UUIDs or integers. ([source](https://typer.tiangolo.com/tutorial/parameter-types/uuid/))
- [Custom Type Converters](https://awesome-repositories.com/f/data-databases/custom-type-converters.md) — Supports custom parsing functions to convert raw command-line input strings into complex objects or specific data types. ([source](https://typer.tiangolo.com/tutorial/parameter-types/custom-types/))
- [Confirmation Validators](https://awesome-repositories.com/f/data-databases/field-validation/confirmation-validators.md) — Ensures input accuracy by requiring users to enter sensitive values twice to confirm they match. ([source](https://typer.tiangolo.com/tutorial/options/prompt/))
- [Numeric Comparison Validators](https://awesome-repositories.com/f/data-databases/numeric-fields/numeric-comparison-validators.md) — Enforces numeric constraints such as minimum and maximum ranges on command-line arguments. ([source](https://typer.tiangolo.com/tutorial/parameter-types/number/))

### Software Engineering & Architecture

- [CLI Entrypoints](https://awesome-repositories.com/f/software-engineering-architecture/application-entrypoints/cli-entrypoints.md) — Configures the primary application interface and global parameters using a function that executes before any subcommands. ([source](https://typer.tiangolo.com/reference/typer/))
- [Dependency Injection](https://awesome-repositories.com/f/software-engineering-architecture/dependency-injection.md) — Injects runtime state and configuration objects into command functions to manage execution flow.
- [Type-Hint-Based Schema Definitions](https://awesome-repositories.com/f/software-engineering-architecture/type-hint-based-schema-definitions.md) — Uses Python type annotations to automatically infer and generate command-line argument parsers and validation logic.
- [Metadata Reflection Frameworks](https://awesome-repositories.com/f/software-engineering-architecture/metadata-reflection-frameworks.md) — Analyzes function signatures and docstrings at runtime to dynamically construct help documentation and parameter configurations.

### Web Development

- [Choice Fields](https://awesome-repositories.com/f/web-development/choice-fields.md) — Validates command-line inputs against a predefined set of allowed choices, rejecting invalid values automatically. ([source](https://typer.tiangolo.com/tutorial/parameter-types/enum/))