Lifeline
Lifeline is a macOS focus timer and productivity tracker. It sits in your menu bar, tracks focused work sessions, breaks, and meetings, and shows your day as a single timeline so you can see where your time actually went.
Lifeline grew out of Saent, the productivity startup I co-founded. After we stopped making hardware, I kept working on the software. It holds a 4.8★ rating on the Mac App Store.
Lifeline also has an open-source companion: lifeline-mcp, an MCP server and CLI that lets Claude, ChatGPT, or any terminal read your session history and control the app remotely.