Parallel branches

Use when dispatching 2+ subagents to edit disjoint files in the same checkout and each slice must become its own stacked PR.

Before dispatch

1. Push the base branch (for example feature/helper-base) and note its SHA as BASE.
2. Give every agent a distinct branch name and an explicit, disjoint file list. Name the shared files nobody may touch.
3. Tell them up front, before any collision report: never run git checkout, switch, stash or reset in the shared worktree, and commit only their own paths.

Commit without moving HEAD (plumbing)

HEAD will be on whichever branch someone checked out first. Agents whose branch is not HEAD build their commit directly on BASE: