addBodyComposition
write
builds a `.fit` binary in memory (`src/util/fit.ts`, a hand-rolled FIT encoder) and uploads it via `client.upload` to `/upload-service/upload`; `weight` validated positive/finite, throws `GarminError` otherwise; passes `client.upload`'s result through unchecked
addBodyComposition(weight, extra?)| Parameter | Type | Optional | Description |
|---|---|---|---|
| weight | number | no | |
| extra | object | yes |
In Claude this is the add_body_composition tool.