I think it's worth mentioning a really basic tool, even if it doesn't have all of the bells and whistles. This is what I carry, sufficient for adjusting something or tightening a loose fastener.

https://www.amazon.com/Eklind-21171-.../dp/B0186KCA2G

They make several different styles with different sizes. They're quite old fashioned, basic, all metal. But they're fairly compact, take a lot of abuse, and last forever. And they won't break the bank. It doesn't take much for a multi-tool to be worth more than my bike.