I carry a chain whip and a cassette tool but not a crescent. My chain whip is homemade from an aluminium bar and the tool for the cassette is made from piece of stainless steel. See the link below. I have had to use it a few times on tours, even with 36 spokes wheels, handbuilt.

https://www.crazyguyonabike.com/doc/...oc_id=6089&v=i