You can build your own decorator that encapsulates the common options:

def common_options(function):
    function = click.option('--unique-flag-1', is_flag=True)(function)
    function = click.option('--bar', is_flag=True)(function)
    function = click.option('--foo', is_flag=True)(function)
    return function

@click.command()
@common_options
def command():
    pass

The way you currently defined it it will work, but the --verbose option belongs to the main command group, so you'd need to call it as python script.py --verbose list (and my_find_command and my_list_command won't receive it as an argument, only cli).

To use the same option across multiple commands without repeating yourself too much, you can just assign it to a variable and then use it twice:

verbose_option = click.option(
    "-v",
    "--verbose",
    count=True,
    default=0,
    help="-v for DEBUG",
)

...

@click.command()
@verbose_option
def foo(verbose):
    ...

@click.command()
@verbose_option
def bar(verbose):
    ...

Unrelated, but while we're at it: There's a simpler way of grouping commands, without having to do cli.add_command(my_find_command): Just use @cli.command() instead of @click.command():

import click

option_verbose = click.option(
    "-v",
    "--verbose",
    count=True,
    default=0,
    help="-v for DEBUG",
)

@click.group()
def cli():
    pass


@cli.command("list")
@option_verbose
@click.option(
    "--list-option",
    help="Special option for list command.",
)
def my_list_command(verbose, list_option):
    print(verbose, list_option)

@cli.command("find")
@option_verbose
@click.option(
    "--find-option",
    help="Special option for find command.",
)
def my_find_command(verbose, list_option):
    print(verbose, list_option)

if __name__ == '__main__':
    cli()

If there's several options you want to apply, you can define your own decorator that calls all those options on the argument:

def common_options(fn):
    return click.option(
        "-v",
        "--verbose",
    )(
        click.option(
            "-n",
            "--dry-run",
        )(fn)
    )

I have found a simple solution! I slightly edited the snippet from https://github.com/pallets/click/issues/108 :

import click


_cmd1_options = [
    click.option('--cmd1-opt')
]

_cmd2_options = [
    click.option('--cmd2-opt')
]


def add_options(options):
    def _add_options(func):
        for option in reversed(options):
            func = option(func)
        return func
    return _add_options


@click.group()
def group(**kwargs):
    pass


@group.command()
@add_options(_cmd1_options)
def cmd1(**kwargs):
    print(kwargs)


@group.command()
@add_options(_cmd2_options)
def cmd2(**kwargs):
    print(kwargs)


@group.command()
@add_options(_cmd1_options)
@add_options(_cmd2_options)
@click.option("--cmd3-opt")
def cmd3(**kwargs):
    print(kwargs)


if __name__ == '__main__':
    group()

If you don't insist on passing something that looks like a list, but simply want to pass multiple variadic arguments, you can use the multiple option.

From the click documentation

@click.command()
@click.option('--message', '-m', multiple=True)
def commit(message):
    click.echo('\n'.join(message))

$ commit -m foo -m bar
foo
bar

The custom class found here, can be adapted to your case.

Using the Custom Class:

To use the custom class, just use the cls parameter to the click.command() decorator like:

@cli.command(cls=AcceptAllCommand)
@click.pass_context
def command1(ctx, **kwargs):
    """Add command1."""
    ...

Test Code:

import click

class AcceptAllCommand(click.Command):

    def make_parser(self, ctx):
        """Hook 'make_parser' and allow the opt dict to find any option"""
        parser = super(AcceptAllCommand, self).make_parser(ctx)
        command = self

        class AcceptAllDict(dict):

            def __contains__(self, item):
                """If the parser does no know this option, add it"""

                if not super(AcceptAllDict, self).__contains__(item):
                    # create an option name
                    name = item.lstrip('-')

                    # add the option to our command
                    click.option(item)(command)

                    # get the option instance from the command
                    option = command.params[-1]

                    # add the option instance to the parser
                    parser.add_option(
                        [item], name.replace('-', '_'), obj=option)
                return True

        # set the parser options to our dict
        parser._short_opt = AcceptAllDict(parser._short_opt)
        parser._long_opt = AcceptAllDict(parser._long_opt)

        return parser


@click.group(chain=True)
@click.pass_context
def cli(ctx, **kwargs):
    """"""


@cli.command(cls=AcceptAllCommand)
@click.pass_context
def command1(ctx, **kwargs):
    """Add command1."""
    ctx.obj['command1_args'] = {}
    for k, v in kwargs.items():
        ctx.obj['command1_args'][k] = v


@cli.command()
@click.argument('command2-argument1', type=str)
@click.pass_context
def command2(ctx, **kwargs):
    """Add command2."""
    print(ctx.obj)
    print(kwargs)


if __name__ == "__main__":
    commands = (
        "command1 --cmd1-opt1 foo --cmd1-opt2 bar command2 hello",
        '--help',
    )

    import sys, time

    time.sleep(1)
    print('Click Version: {}'.format(click.__version__))
    print('Python Version: {}'.format(sys.version))
    for cmd in commands:
        try:
            time.sleep(0.1)
            print('-----------')
            print('> ' + cmd)
            time.sleep(0.1)
            cli(cmd.split(), obj={})

        except BaseException as exc:
            if str(exc) != '0' and \
                    not isinstance(exc, (click.ClickException, SystemExit)):
                raise

Results:

Click Version: 6.7
Python Version: 3.6.3 (v3.6.3:2c5fed8, Oct  3 2017, 18:11:49) [MSC v.1900 64 bit (AMD64)]
-----------
> command1 --cmd1-opt1 foo --cmd1-opt2 bar command2 hello
{'command1_args': {'cmd1_opt1': 'foo', 'cmd1_opt2': 'bar'}}
{'command2_argument1': 'hello'}
-----------
> --help
Usage: test.py [OPTIONS] COMMAND1 [ARGS]... [COMMAND2 [ARGS]...]...

Options:
  --help  Show this message and exit.

Commands:
  command1  Add command1.
  command2  Add command2.