Architect — What Gets Built

An engineer handed a brief does not start typing. They work out what the thing is made of first: what screens exist, what objects, who may touch them, where the rules are enforced, and what gets built in what order. That thinking is a document, and this skill writes it.

One output, build/<surface>/plan.md. No code, no scaffold, no folders on disk beyond the plan itself.

Three reasons it is its own skill rather than a step inside the build:

1. Its own context. Architecture decided well needs the whole brief in view. A build holding half-written source cannot also hold that.
2. A human approves it. The cheapest moment to catch a wrong assumption is before any code exists, and a plan is short enough to actually read.
3. It makes "finished" countable. The checklist has one row per use case. The build is done when every row is ticked, not when it looks done.