I spent this week ripping out the fixed-routine part of a SwiftUI workout app and replacing it with a small AI planning system.
Not a chatbot bolted onto the side. The app asks for goals, reads a compact set of real constraints, calls Claude through a backend function, then stores the resulting 7-day plan locally in SwiftData.
The old version was simple: two hardcoded push/pull routines and a fixed exercise library. Fine for a prototype, but too rigid. If the user only has dumbbells up to 25kg, trains three days a week, and had a rough sleep week, the app needs to know that before it suggests anything.
The new flow is:
user configures equipment once
