Session transcripts hold the code and the reasoning behind it, a better review source than the diff alone. Gage, an Apache 2 CLI and TUI written in Rust, scans Claude Code transcripts and files issues where every claim cites lines in the session record. You can fix an issue, close it as skipped, or hand it back to Claude Code to resolve.
The author built it after waving through a risk Claude flagged mid-session, which broke a feature the commit didn't show. Scans run under your Claude login, so on a subscription they count against plan limits, and on usage-based billing they cost about $0.50 to $1.00 per session. Running it daily, the author puts his spend at roughly $2 per issue resolved.