Is there a list of pre-installed command-line tools for macOS? I'm currently in the process of developing some shell scripts but have run into a problem: whilst I am able to execute numerous commands on my Mac, when I try to run it on other people's computers I get Command not found errors indicating that they do not have the specific command line tools installed.

It is my belief that many of these tools come as a result of installing Xcode and other package managers like Homebrew. My question is: is there a list or another way of finding out if a specific command (tool) is pre-installed on a standard Mac computer (without Xcode installed) without having to manually test it on someone else's computer?

For example, this post hints that git is pre-installed which is only the case if you have installed Xcode, otherwise, git is unavailable. 

P.S. For my specific case, I am wondering if hexdump is pre-installed or not (without Xcode)
Actually it looks like there is a simple way to know that.

At Terminal prompt hit the Escape (or TAB) twice

It will ask you if you want to Display all 1527 possibilities? (y or n).

Or here https://ss64.com/osx/