but the difference between you and an agent is that you naturally know the history of the project if you have worked on it. the AI doesnt.

so true!

1) commit messages often capture the "why" something changed - versus the code/tests which focus on the what/how for right now.

2) when you have a regression being able to see the code before it was introduced and the code which was changed at the same time is very helpful in understanding the developer's intent, blindspots in their approach, etc.