Everything you can do on the canvas right now. Start at the top, work your way down. Each workflow has copy-pasteable content so you can test immediately.
Does clicking into blocks feel instant? Can you type without friction?
Do the loading skeletons give you confidence something is happening?
When a new card appears from an action, does the position feel right?
Does spatial context actually work? Does the Chat reference nearby content?
After 10 minutes, does your canvas feel organized or chaotic?
Would you come back tomorrow to keep building on this canvas?