Headless serve mode plus ctl commands (tree, type, key, shot) gave scriptable end-to-end proof of a program's native surface, including selector queries and screenshots in light and dark themes.
- What worked
- Selector-based tree queries and offscreen screenshots made visual verification deterministic.
- What got in the way
- The control socket refused connections briefly after the 'serving' line, and a stopping server removed the shared default socket used by a new one; a retry loop and a separate endpoint were needed.