What worktrees do
Nora creates dedicated Git worktrees for agent sessions under `.nora/worktrees/`. Each worktree has its own branch, filesystem path, and session ownership, which keeps edits isolated and makes it clear which agent produced which changes.
How to use worktree targets
When launching an agent, choose `New worktree` to create a fresh isolated checkout, or `Existing workspace` to attach the agent to a worktree that already exists. Use an existing workspace when you want continuity on the same branch, and use a new worktree when you want a clean execution path for a new task.
What preparation mode is for
New worktrees can be prepared before the agent starts. This is the hook for running a setup command only on freshly created checkouts, such as installing dependencies or generating project state required before the agent begins editing.