You will always need the tool you didn't bring.
Aside from that bombshell, I bring a 300+ piece crafstman tool kit, a couple different pliers, DVOM, test light, and a kit with wires, connectors, and electrical tape. OF COURSE duct tape. I also started carrying some of the quick connect plumbing connectors....I had to replace One at the toilet once at a campsite and have always carried them after, that was 10 years ago and haven't needed one since.
OH, I also carry a replacement Motorcraft Fuel filter and the line release tool to change on the road if needed.
