Klix

CLI interfaces that just click.

Klix is a Python framework for building polished, interactive command-line applications. It combines command routing, typed session state, prompt-driven input, rich rendering, middleware, events, and lightweight layout primitives into one developer-facing toolkit.

Why Klix

Klix is built for developers who want more than print() and argparse, but do not want to hand-roll a terminal framework every time they start a new tool.

It is a framework, not a finished app. You define the commands, state, UI, and flow. Klix provides the runtime pieces that make those tools feel deliberate instead of improvised.

Key Features

• Command-first app model with decorators and first-class Command objects
• Typed session state for per-run data and persisted workflows
• Prompt-driven input powered by prompt_toolkit
• Rich terminal rendering with sensible fallback behavior
• Reusable UI helpers for tables, panels, spinners, selectors, forms, and streaming
• Middleware and lifecycle events for cross-cutting behavior
• Lightweight layout regions for headers, status lines, and structured screens
• Built-in scaffold CLI via klix init mytool

Demo

Minimal command flow:

$ python examples/minimal.py
Minimal
Try /help, /deploy staging, /ask, /login, /markdown, or /exit.

> /deploy staging --force
Deploying to staging in forced mode

> /help
/deploy <environment> [--force]      Deploy to an environment
/ask                                 Prompt for free-form input
/login                               Collect credentials interactively
/markdown                            Render markdown output

> /exit

Chat-style UI example:

$ python examples/chat_ai.py
Klix Assistant
Talk to the demo like a ai chat app. Type normal text to send a message...

You > explain terminal UX
Assistant: terminal UX looks manageable. I would break it into a small core...

You > /theme
Assistant: Theme switched to light.

Installation

For local development:

python -m pip install -e .

This installs:

• the klix Python package
• the klix scaffold command

After installation:

klix

Expected output:

Usage: klix init <name>

Quickstart

Create a small Klix app:

from dataclasses import dataclass

import klix


@dataclass
class DemoState(klix.SessionState):
    runs: int = 0


app = klix.App(
    name="demo",
    version="0.1.0",
    description="Small Klix example",
    state_schema=DemoState,
)


@app.on("start")
def on_start(session: klix.Session) -> None:
    session.ui.print("Demo is ready. Try /hello or /exit.", color="muted")


@app.command("/hello", help="Say hello")
def hello(session: klix.Session) -> None:
    session.state.runs += 1
    session.ui.print(f"Hello from Klix. Run #{session.state.runs}", color="success")


if __name__ == "__main__":
    app.run()

Run it:

python main.py

Core Concepts

• App: the composition root for commands, middleware, events, theme, and persistence
• Session: per-run context holding state, metadata, UI, and input history
• Router: parses slash commands and validates typed arguments
• InputEngine: prompt handling, input modes, and interactive terminal behavior
• Renderer: rich-aware output with fallback modes for simpler terminals
• UI: the main application-facing namespace for input, output, layout, and streaming
• Layout: lightweight persistent regions for header, main output, and status

If you want the deeper architectural walkthrough, start with docs/index.md and then docs/concepts/architecture.md.

Example Command Usage

Typed command with arguments:

from pydantic import BaseModel


class DeployArgs(BaseModel):
    environment: str
    force: bool = False


@app.command("/deploy", args_schema=DeployArgs, help="Deploy the service")
def deploy(args: DeployArgs, session: klix.Session) -> None:
    session.ui.print(
        f"Deploying to {args.environment} (force={args.force})",
        color="warning",
    )

Interactive command with reusable UI components:

@app.command("/release", help="Run a guided release flow")
async def release(session: klix.Session) -> None:
    version = await session.ui.input.text("Version", placeholder="1.2.3")
    target = await session.ui.input.select(
        ["staging", "production"],
        label="Environment",
    )
    confirmed = await session.ui.input.confirm(
        f"Release {version} to {target}?",
        default=False,
    )

    if not confirmed:
        session.ui.print("Release cancelled.", color="warning")
        return

    session.ui.output.panel(
        f"Released {version} to {target}",
        title="Release Complete",
        border_color="success",
    )

Examples In This Repository

• examples/minimal.py: compact command-oriented starter app
• examples/full_demo.py: broader framework walkthrough with persistence and middleware
• examples/chat_ai.py: Gemini-style conversational UI demo
• examples/ui_showcase.py: reusable input and output component showcase

Documentation

The full docs live in docs/.

Recommended starting points:

• Getting Started
• Installation
• Quickstart
• Architecture
• Building Your First CLI
• API Reference

Contributing

Contributions are welcome. Good issues, focused pull requests, example improvements, and documentation fixes all help.

Start with CONTRIBUTING.md for local setup, project structure, and contribution guidelines.

License

Klix is licensed under the Apache License 2.0.