Watch & Read: CLI Frameworks

Your scripts have used input() for user interaction. That works when you're using a tool interactively. But real automation is different.

Imagine generating prompts for 20 shots from a CSV file. With input(): type each one manually, wait, type the next. With a CLI tool:

python dvp.py batch my_shots.json --save

One command. All 20 shots. All platforms. Done in seconds. That's automation — and that's what CLI tools unlock.

CLI tools also integrate with shell scripts, cron jobs, and other tools. input() can't do that.

Read these three sections from the Typer Official Tutorial:

1. First Steps — creating a basic command
2. CLI Arguments — required positional inputs
3. CLI Options — optional flags with defaults

Typer was built by the same developer as FastAPI. The design philosophy is the same: use Python type hints to define behavior, and the framework generates validation, help text, and shell completion automatically.

# In CLI tools, there are two kinds of inputs:

# ARGUMENT — required, positional.
# python dvp.py generate "Golf swing at sunset"
#                         ^^^^^^^^^^^^^^^^^^^^ this is an argument

# OPTION — optional, named with --flag.
# python dvp.py generate "Golf swing" --platforms Kling,Runway --save
#                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ these are options

import typer
app = typer.Typer()

@app.command()
def generate(
    shot: str,                          # required argument — no default
    platforms: str = typer.Option("Kling,Runway,Veo"),  # optional flag
    save: bool = typer.Option(False),   # --save flag
):
    """Generate AI prompts for a shot."""
    typer.echo(f"Generating for: {shot}")

The docstring becomes the command's help text. Type annotations and Option() definitions generate the options list. Run any Typer command with --help and you get a full usage guide — for free, without writing it yourself.

python dvp.py generate --help
# Outputs something like:
#
# Usage: dvp.py generate [OPTIONS] SHOT
#
#   Generate AI prompts for a shot.
#
# Arguments:
#   SHOT  [required]
#
# Options:
#   --platforms TEXT       [default: Kling,Runway,Veo]
#   --save / --no-save     [default: no-save]
#   --help                 Show this message and exit.

app = typer.Typer(name="dvp", help="DVP Prompt Vault tools.")

@app.command()
def list(): ...

@app.command()
def generate(): ...

@app.command()
def search(): ...

# Run them:
# python dvp.py list
# python dvp.py generate "Golf swing"
# python dvp.py search golf
# python dvp.py --help  (shows all commands)