func printClassifyUsage() {
	fmt.Fprintf(os.Stderr, "Usage: skraak calls classify [options]\n\n")
	fmt.Fprintf(os.Stderr, "Interactive TUI for reviewing and classifying bird call segments.\n")
	fmt.Fprintf(os.Stderr, "Reads .data files (AviaNZ format) and presents segments for labelling\n")
	fmt.Fprintf(os.Stderr, "with spectrogram display and audio playback.\n\n")
	fmt.Fprintf(os.Stderr, "Options:\n")
	fmt.Fprintf(os.Stderr, "  --folder <path>       Path to folder containing .data files (required, or --file)\n")
	fmt.Fprintf(os.Stderr, "  --file <path>          Path to a single .data file (required, or --folder)\n")
	fmt.Fprintf(os.Stderr, "  --reviewer <name>     Reviewer name for labelling attribution (required)\n")
	fmt.Fprintf(os.Stderr, "  --bind <key=value>    Key binding for species label (required, repeatable)\n")
	fmt.Fprintf(os.Stderr, "  --filter <name>       Filter name to scope which segments to review (optional)\n")
	fmt.Fprintf(os.Stderr, "  --color               Enable color spectrogram output\n")
	fmt.Fprintf(os.Stderr, "  --sixel               Use Sixel protocol for spectrogram images\n")
	fmt.Fprintf(os.Stderr, "  --iterm               Use iTerm2 protocol for spectrogram images\n")
	fmt.Fprintf(os.Stderr, "  --img-dims <int>      Image dimensions in characters (optional)\n")
	fmt.Fprintf(os.Stderr, "\nBind format:\n")
	fmt.Fprintf(os.Stderr, "  --bind k=Species           Bind key 'k' to label as Species (any call type)\n")
	fmt.Fprintf(os.Stderr, "  --bind d=Species+CallType  Bind key 'd' to label as Species with specific call type\n")
	fmt.Fprintf(os.Stderr, "\nExamples:\n")
	fmt.Fprintf(os.Stderr, "  # Classify kiwi calls in a folder\n")
	fmt.Fprintf(os.Stderr, "  skraak calls classify --folder /path/to/data --reviewer dave \\\n")
	fmt.Fprintf(os.Stderr, "    --bind k=Kiwi --bind d=Kiwi+Duet --bind n=NotBird --sixel\n\n")
	fmt.Fprintf(os.Stderr, "  # Classify a single file with filter\n")
	fmt.Fprintf(os.Stderr, "  skraak calls classify --file /path/to/file.data --reviewer dave \\\n")
	fmt.Fprintf(os.Stderr, "    --filter opensoundscape-kiwi-1.2 --bind k=Kiwi --color\n")
}

			fmt.Fprintf(os.Stderr, "Error: unknown flag: %s\n", arg)

			fmt.Fprintf(os.Stderr, "Error: unknown flag: %s\n\n", arg)
			printClassifyUsage()

	missing := []string{}

		fmt.Fprintf(os.Stderr, "Error: --folder or --file is required\n")
		os.Exit(1)

		missing = append(missing, "--folder or --file")

		fmt.Fprintf(os.Stderr, "Error: --reviewer is required\n")
		os.Exit(1)

		missing = append(missing, "--reviewer")

		fmt.Fprintf(os.Stderr, "Error: at least one --bind is required\n")

		missing = append(missing, "--bind")
	}
	if len(missing) > 0 {
		fmt.Fprintf(os.Stderr, "Error: missing required flags: %v\n\n", missing)
		printClassifyUsage()