Pretty much everyone saying worktrees but I lean heavily on hot-reloading of both backend and frontend (to actually see what I'm doing) so it's too annoying to deal with dependencies and ports when things are isolated. Instead I keep everything on the main branch and just make sure to keep tasks pretty separate in scope, e.g. add this API route vs. fix this layout issue, so they don't step on each other. When I consider something done I have the agent commit what it worked on and start a new one.