I've been attaching to my commit messages a Git Trailer [1] of the Session UUID from the Claude Code conversation that created that commit.

It allows Claude to look back into the session where a change was made and see the decisions made, tradeoffs discussed and other history not captured by code, tests.

[1] https://git-scm.com/docs/git-interpret-trailers

I had a similar experience refactoring a large codebase• The only thing that made it possible was that each commit message had a JIRA ticket number tying it to a requirement or task. I could find the people behind the business logic and ask them about it.

the recursive-mode workflow has full traceability, including why decisions were made, what the original requirement was, what the previous state was, etc. https://recursive-mode.dev/introduction