This is the route I went for making Claude Code and Codex conversation histories local and queryable by the CLIs themselves.

Create the DB and provide the tools and skill.

This blog entry explains how: https://contextify.sh/blog/total-recall-rag-search-claude-co...

It is a macOS client at the present but I have a Linux-ready engine I could use early feedback on if anyone is interested in giving it a go.