# cli.py
parser.add_argument(
    '--schema',
    type=str,
    metavar='SCHEMA',
    help="Schema to use: 'auto' for auto-detection, or schema name"
)

parser.add_argument(
    '--list-schemas',
    action='store_true',
    help='List all available schemas and exit'
)

def main(argv=None):
    args = parser.parse_args(argv)
    
    # Handle --list-schemas
    if args.list_schemas:
        from fetcharoo.schemas import get_all_schemas
        schemas = get_all_schemas()
        if schemas:
            print("Available schemas:")
            for name, schema in sorted(schemas.items()):
                desc = schema.description or "No description"
                print(f"  {name:20} {desc}")
        else:
            print("No schemas registered.")
        return 0
    
    # Pass schema to download function
    result = download_pdfs_from_webpage(
        url=args.url,
        # ... other args ...
        schema=args.schema,
    )