add-downloader

name	add-downloader
description	Scaffold a new video downloader implementation following the Downloader Protocol.
allowed-tools	Read, Write, Edit, Glob, Grep
argument-hint	["downloader-name"]

Add a new downloader

Create a new downloader named $ARGUMENTS following existing patterns.

Steps

1. Read kinescope/downloaders/base.py to understand the Downloader Protocol
2. Read kinescope/downloaders/n_m3u8dl.py and kinescope/downloaders/ffmpeg.py as reference implementations
3. Create kinescope/downloaders/$ARGUMENTS.py with:
   • A class that implements the download(**kwargs) -> bool interface
   • A static is_available() method to check if the tool is installed
   • Proper error handling (return False on failure, raise DownloadError for fatal issues)
4. Read kinescope/runner.py and add the new downloader to the fallback chain in process_single()
5. Verify all files compile: python3 -m py_compile <file>

Conventions

• Never call sys.exit() — raise exceptions or return False
• Use TMP_DIR = "/tmp/kinescope" for temp files
• Binary lookup: shutil.which() first, then ~/bin/ fallback
• Match the keyword-only argument signature from base.py