> Historical agent handoff. The integrated composition and current test status are documented in `docs/FIRST-DEVICE-PROTOTYPE.md` and `docs/VALIDATION.md`. Proposed wiring below has been incorporated or superseded.

# MotionCapture integration proposal

Owner: workstream C (`feat/wrist-motion`).

This change introduces a watch-only adapter boundary without changing the
RemoteCore envelope. `MotionCaptureService` emits `GestureCore.GestureRecognition`
values (semantic `RemoteCommand`, confidence, and a local monotonic timestamp)
to the watch shell. It never creates envelopes, carries TV identity, or retries
commands.

## Proposed target membership

The integrator should add `Adapters/MotionCapture/Sources/MotionCapture/*.swift`
to a watchOS-only target that depends on the `GestureCore` package product. The
pure classifier and its tests remain in `Packages/WristivoKit` and therefore
build on macOS/iOS/watchOS. Core Motion must not be imported by the package.

## Lifecycle and permission contract

The watch shell calls `start(sessionID:)` only after calibration and explicit
foreground arming. `stop(reason:)` is idempotent and must be called for scene
inactivity, relay loss, target/session changes, expiry, cancellation, or sensor
failure. A subsequent start creates a fresh neutral baseline. Hardware
availability and start-handler failures are surfaced as typed errors; no
permission denial is treated as an empty sample stream. The watch target needs
the platform's truthful motion purpose string in its host configuration.

## Migration and tests

No wire/schema migration is required. Existing watch code can initially ignore
the new service and continue using touch controls. The integrator must add the
watch target membership and motion purpose string, then run the package tests
and a physical permission/foreground suspension check. Simulator and synthetic
traces validate logic only; no hardware recognition claim is made by this
workstream.