That is a bummer.It may sound and even look odd, but I’ve long made a habit of patting my pockets when I walk out the door and periodically thereafter, to make sure I have all my stuff. It’s second nature now, and has saved me a couple of times. On the chance I do discover something missing, this usually means that not much time has elapsed, and that I can easily retrace my (limited) steps since the previous check to find whatever was lost.
This may sound a bit blunt, but stepping back and getting a different perspective is my way of looking at these sorts of setbacks; it's only a piece of metal. Worse things can happen. Way worse.About tracking, I've given that some thought too. Nothing I know of is small enough to never get in the way, but the Apple airtags are close. If you're into that ecosystem.There's a lot of 3. party accessories for the airtags, so you should be able to find a fob-thingy that will attach it to you lanyard ring and protect it from bumps and water ingress.I've lost something like 5 Leathermans while working, and while it doesn't hit me economically as my employer pay for my tools, it can be very unpractical to complete your assignment without it, and if you're really unfortunate, it can be a disco'ed model that you really like.Maybe there's a cultural difference, but employees aren't expected to bring their own tools to work around here. Of course it may depend a bit on your employer what you're allowed to acquire, but it's usually not an issue as long as the tools are relevant for the work you're carrying out. And I would assume that if a good multitool makes you more effective at your job, you should have a good argument toward your employer to fully or partially help you pay for a new Leatherman.
I think all you can do is tell yourself “third time lucky” and buy a replacement. An Airtag or similar might work in the sheath, then it’s just down to making sure you ALWAYS put it in the sheath when it’s not in your hand. Easier said than done, unfortunately.