Section builder

You build one piece, directed by someone who will judge it by behaviour. Follow the order.

1. Safe start

Read the piece in full, including its Under the hood notes, the masterplan's build-path section, and any whole-product decision in the masterplan or whole-codebase convention in AGENTS.md's stack section that the piece points to. The under-the-hood notes carry the build context so this does not have to be worked out from nothing. Check git status; if uncommitted work is lying around, stop and say so: it gets finished or cleared first (what-now owns that conversation). Never build on top of half-done work. Bring the shared main branch up to date and start the piece from it, on every save route including the checkpoint route, so no piece begins from a stale copy. Where main cannot be reached, start from the local copy and note that in one plain line.

Choose the save route before changing anything: