# Handoff: right-size the exercise library by functional coverage

Repo: `~/Documents/indie/Workouts`. Read `Exercise Library/SYSTEM.md` first
(motion format, props, visual language), then one machine motion
(`Leg Press/motion.json`) and one bodyweight motion (`Bird Dog/motion.json`)
as templates, one `info.md` (`Leg Press/info.md`) plus its parser
(`Workouts/ExerciseFigure/ExerciseInfo.swift` — it parses a fixed shape, not
general Markdown), and `render.py` (`--sheet`, `--strict`, `--orbit`,
`--export`, `--fixtures`).

## The question this session answers

Not "how many exercises" but "which movement patterns can a user not log?"
The picker (`ExercisePickerView`) lists exactly the bundled library names and
there is no free-text fallback — the library is the app's **closed catalog**.
A missing pattern is a hard wall, not a cosmetic gap. Build the coverage
model, audit against it, then author the gap-fillers in priority order.

## The coverage model (starting point — refine it, don't rubber-stamp it)

A movement-pattern × modality matrix. Patterns: squat, hinge, lunge,
horizontal push, vertical push, horizontal pull, vertical pull, elbow
flexion, elbow extension, shoulder raise (lateral/rear), hip ab/adduction,
calf, core anti-extension, core rotation, core lateral, core flexion,
mobility/warm-up. Modalities: machine, free weight (barbell/dumbbell),
bodyweight/floor. A cell needs an exercise only if real programs train that
pattern that way — the test for "done" is that a typical gym-goer (machine
circuit, free-weight lifter, or home/bodyweight) can build their whole
program from the picker. Write the filled matrix into SYSTEM.md (or a
COVERAGE.md beside it) so future additions are judged the same way.

## What a rough audit already shows (verify, then prioritize)

- **Hinge: zero coverage in any modality** — no Deadlift, Romanian Deadlift,
  Glute Bridge, or Hip Thrust. The single biggest hole; glutes are basically
  untrained by the current catalog.
- **No lunge pattern** (Lunge / Split Squat).
- **Bodyweight column missing its canon**: Squat, Push-Up, Pull-Up.
- **Free-weight column completely empty** — zero barbell/dumbbell exercises.
  The `dumbbell` prop type exists in both renderers but has never been used
  by a motion; its first real use may shake out bugs.
- **Shoulder raise**: no Lateral Raise (machine Shoulder Press only).
- **Core flexion**: no plain Crunch (machine Abdominal only).
- Memory notes a desired "morning wake-up" mobility set (Cat-Cow exists;
  neck rolls, arm circles, etc.) — decide whether it's this session or the
  next phase.

Filling these modestly lands around 40–46 total (currently 22) — "double the
library" is the outcome, but the matrix decides which ones and in what order:
hinge first, then lunge + bodyweight canon, then free weights, then
isolation/mobility.

## Authoring workflow, per exercise

- New folder `<Name>/` with `motion.json` + `info.md`. The folder/`name`
  string is user-facing (picker + run screen) — match the existing naming
  register.
- Pose keyframes in anatomical angles per SYSTEM.md; run
  `python3 render.py --strict "<Name>"` (ROM violations are data bugs; a few
  legacy warnings exist in old motions, add none), eyeball `preview.gif` AND
  `orbit.gif` — every exercise orbits in-app now, so check ±45°/90°/180°,
  not just the authored view.
- Machines need props: scene slabs carry `z`/`depth` (see SYSTEM.md props
  section), `bar`/`pad`/`roller`/`cable` ride joints. Free weights are
  usually just a `bar` (with `plateR`) or `dumbbell` at the hands.
- `info.md` must follow the parsed shape: `# Title`, summary paragraph,
  the `**Category:** / **Type:** / **Targets:** / **Prescription:**` bullets,
  then `## Setup / Execution / Cues / Common Mistakes / Progression`.
  **Machine exercises' `Type:` must start "Machine-based"** — that prefix is
  what shows the machine-settings UI (`ExerciseInfo.isMachineBased`).

## Invariants — do not break

- **Data-only expansion.** New exercises need zero Swift changes; if you find
  yourself touching the schema or solver, stop and re-read SYSTEM.md — and
  any schema change must land in `render.py`/`kinematics.py` and the Swift
  port in lockstep, fixtures regenerated.
- `WorkoutsTests/ExerciseMotionTests.swift` asserts
  `fixtures.exercises.count == 22` — bump it to the new count and regenerate
  with `python3 render.py --fixtures`. `allBundledMotionsBuildTimelines`
  covers new motions automatically.
- Starter splits and their fixed-ULID seeds are frozen — adding library
  exercises must not touch `StarterSplits/` or `Workouts/Seed/`.
- Every exercise ships both files: a motion with no `info.md` renders a blank
  reference page in Settings → Library.

## Verification workflow

`python3 render.py --strict` (whole library) + `--sheet` and eyeball;
`--orbit` for each new machine; `python3 render.py --export` then
`python3 render.py --fixtures`; `xcodebuild test -scheme Workouts
-destination 'platform=iOS Simulator,name=iPhone 17 Pro'
-only-testing:WorkoutsTests` (48 green today; count assertion updated);
`xcodebuild build -scheme "Workouts Watch App" -destination
'generic/platform=watchOS Simulator'`. If test results ever contradict the
source, suspect a stale incremental build — nuke DerivedData and rerun.
One end-user CHANGELOG.md sentence per the app-changelog skill (e.g. the
library doubles with deadlifts, lunges, push-ups, dumbbells…), README
key-features line if it names library scope. Commit in reviewable batches
(the coverage model + audit first, then exercises by pattern group), push,
delete this file in the final commit.

## Judgment calls you're empowered to make

The final matrix rows and which cells count as "required"; the exact
exercise picks per gap and their names; whether the mobility/"morning
wake-up" set is in scope or explicitly deferred to the next phase; per-
exercise camera yaw and prop minimalism (schematic silhouettes, never scale
models).