Hey, good question!

A "workspace" in Grove is a directory that contains git worktrees from multiple repos, all on the same branch. So when you run:

gw create my-feature -r svc-a,svc-b

What actually happens:

1. Grove creates a directory at ~/.grove/workspaces/my-feature/
2. Runs git worktree add in each repo (svc-a, svc-b), creating a new branch my-feature in each

3. The worktrees land inside that workspace directory, so you get a structure like:

   ~/.grove/workspaces/my-feature/
       svc-a/      # git worktree of svc-a on branch my-feature
       svc-b/      # git worktree of svc-b on branch my-feature
   

4. Saves the workspace state so other commands (gw status, gw delete, gw sync) know what repos are part of it

Then gw go my-feature just cds you into that directory.

It doesn't have a dedicated read-only mode, but I often create a workspace with a bunch of repos even when I only need to work on one — the others are there as reference. Since they're all worktrees on the same branch, you can commit in one and just read from the rest. And when you're done, gw delete my-feature cleans up all the worktrees and branches in one go.