Mostly the official Claude extension in VS Code, with many windows open: one per project I'm working on, plus one per group of projects, basically the parent folder for cross-project refactoring. One window holds all the AppStore apps, another all the MCP servers, and so on.

Then I'm basically smashing VS Code's quickSwitchWindow shortcut to rotate through the sessions round-robin. It's clearly not perfect, I'm obviously not maximizing each session, but since I'm close to hitting my rate limits anyway I haven't looked for further optimization. Maybe I should.