For the sake of convenience, when you enter a bunker to play a shot you like to bring the rake with you. It makes it easier to tend to the sand after completing your stroke.

Your partner says this is illegal. You say it's not. Who's right?

You are.

As long as the rake is not used to test the condition of the sand prior to playing your shot, there's nothing wrong with placing the rake in the bunker (see Exception 1 to Rule 13-4).

Likewise, the rules do no prohibit placing other clubs in the bunker, as long as they are not used to test the sand conditions.

The same applies to water hazards. Of course, the rake or clubs must not have any effect on your ball or the lie.