chore(withings): document full meastype mapping + API coverage audit

Adds src/lib/withings/mapping.md as the single source of truth for the meastype → MeasurementType table that the client.ts MEASURE_TYPE_MAP mirrors, and .planning/research/withings-api-coverage.md as the full audit of the Withings public API surface (Measure, Sleep, Heart, Activity, Workouts, User, Notify) against HealthLog's ingestion. The audit scores each gap on user-value / effort / schema-impact and slots additions into v1.4.25 (cheap mappings), v1.4.26 (sleep + activity sync, body composition expansion) and v1.5 (ECG, AFib, workouts).
2026-11-10 13:22:14 +00:00 · 2026-05-14 13:21:28 +02:00
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+# Withings API — Full Surface Coverage Audit
+
+Date: 2026-05-14
+Status: Research + v1.4.25 implementation plan. Wave produces atomic commits per new mapping.
+Baseline: HealthLog v1.4.25-dev / `develop`. Withings code lives in `src/lib/withings/`.
+
+This document audits **every** Withings public API endpoint and meastype against HealthLog's ingestion path, scores the gaps, and lists what we ship in v1.4.25 vs defer to v1.4.26 / v1.5.
+
+---
+
+## Section 1 — Inventory of HealthLog's current Withings surface
+
+Current ingestion path (`src/lib/withings/client.ts` → `MEASURE_TYPE_MAP`):
+
+| meastype | Withings name | HealthLog `MeasurementType` | Unit (DB) | Notes |
+|---|---|---|---|---|
+| 1 | Weight | `WEIGHT` | kg | ✅ Body+, Body Cardio, Body Comp, Body Scan |
+| 6 | Fat Ratio | `BODY_FAT` | % | ✅ Body+ family |
+| 9 | Diastolic Blood Pressure | `BLOOD_PRESSURE_DIA` | mmHg | ✅ BPM Connect, BPM Core, BPM Vision |
+| 10 | Systolic Blood Pressure | `BLOOD_PRESSURE_SYS` | mmHg | ✅ same |
+| 11 | Heart Pulse | `PULSE` | bpm | ✅ from BPM cuffs + scales |
+| 54 | SpO2 (ScanWatch / pulse-ox) | `OXYGEN_SATURATION` | % | ✅ ScanWatch / BPM Vision |
+| 77 | Hydration / Water Mass | `TOTAL_BODY_WATER` | kg | ✅ Body Comp, Body Scan (kg of water) |
+| 88 | Bone Mass | `BONE_MASS` | kg | ✅ Body Comp, Body Scan |
+
+Endpoints actually used:
+
+| Endpoint | Action | Status |
+|---|---|---|
+| `POST /v2/oauth2` | `requesttoken` (exchange + refresh) | ✅ implemented |
+| `POST /measure` | `getmeas` | ✅ implemented (paged with `offset` until `more=false`) |
+| `POST /notify` | `subscribe` (appli=1) | ✅ implemented — but ONLY appli=1 (weight) |
+| `POST /notify` | `revoke` | ✅ implemented |
+
+OAuth scope requested: `user.metrics` — see `getAuthorizationUrl()`. That's the right minimum for measurements; it does NOT cover activity (`users.activity`), sleep events (`user.sleepevents`), or user info (`user.info`).
+
+---
+
+## Section 2 — Full Withings public surface
+
+### 2.1 Measure API — `POST /measure`
+
+Withings' core "scalar reading" endpoint. Returns `measuregrps` keyed by `meastype` int. Below is the meastype catalog as published in the Withings developer guide (cross-referenced against the API reference and the All Available Health Data table). All require `user.metrics` scope.
+
+Coverage legend: ✅ ingested today / 🟡 enum exists but not wired / ⚠️ wire to existing bucket / ❌ no enum, would need additive schema change.
+
+| meastype | Withings name | Unit (raw) | HealthLog status | Target bucket | Notes |
+|---|---|---|---|---|---|
+| 1 | Weight | kg | ✅ ingested | `WEIGHT` | |
+| 4 | Height | m | ❌ no enum | (User profile field) | One-shot. Belongs in `User` profile (display unit), not `Measurement`. Skip-with-rationale. |
+| 5 | Fat Free Mass | kg | ❌ no enum | (new `FAT_FREE_MASS`) | Body+ family ships this. Algorithmically = weight − fat mass. Defer to v1.4.26 with schema enum addition. |
+| 6 | Fat Ratio (body fat %) | % | ✅ ingested | `BODY_FAT` | |
+| 8 | Fat Mass Weight | kg | ❌ no enum | (new `FAT_MASS`) | Body+ family. Mass form of `BODY_FAT` (kg, not %). Defer. |
+| 9 | Diastolic BP | mmHg | ✅ ingested | `BLOOD_PRESSURE_DIA` | |
+| 10 | Systolic BP | mmHg | ✅ ingested | `BLOOD_PRESSURE_SYS` | |
+| 11 | Heart Pulse | bpm | ✅ ingested | `PULSE` | From BPM cuff + scale. Scale = standing HR. |
+| 12 | Temperature (legacy Thermo) | °C | 🟡 enum exists | `BODY_TEMPERATURE` | **Wire in v1.4.25.** First-gen Thermo (WBT01). |
+| 35 | SpO2 (legacy code) | % | 🟡 enum exists | `OXYGEN_SATURATION` | **Wire in v1.4.25.** Some Withings devices report `35` instead of `54`. |
+| 54 | SpO2 (ScanWatch / pulse-ox) | % | ✅ ingested | `OXYGEN_SATURATION` | |
+| 71 | Body Temperature (Thermo / core) | °C | 🟡 enum exists | `BODY_TEMPERATURE` | **Wire in v1.4.25.** Current-gen Thermo. |
+| 73 | Skin Temperature | °C | ❌ no enum | (new `SKIN_TEMPERATURE`) | ScanWatch dermal reading; distinct from core body temp. Defer to v1.4.26 with new enum (collapsing into `BODY_TEMPERATURE` would corrupt analytics — surface temps run 30–34 °C, core ≈37 °C). |
+| 76 | Muscle Mass | kg | ❌ no enum | (new `MUSCLE_MASS`) | Body+ family. Defer to v1.4.26. |
+| 77 | Hydration / Water Mass | kg | ✅ ingested | `TOTAL_BODY_WATER` | |
+| 88 | Bone Mass | kg | ✅ ingested | `BONE_MASS` | |
+| 91 | Pulse Wave Velocity | m/s | ❌ no enum | (new `PULSE_WAVE_VELOCITY`) | Body Cardio / Body Scan exclusive. Not in US. Defer to v1.4.26. |
+| 123 | VO2 max | mL/(kg·min) | 🟡 enum exists | `VO2_MAX` | **Wire in v1.4.25.** ScanWatch series. |
+| 130 | Atrial Fibrillation (PPG) | enum 0/1 | ❌ no enum | (defer — needs event model) | Algorithmic AFib flag from PPG window. Defer to v1.5 with a dedicated `CardiacEvent` model. |
+| 135 | QRS interval (auto from ECG) | ms | ❌ no enum | (defer — clinical) | ScanWatch / BPM Vision. Defer to v1.5. |
+| 136 | PR interval | ms | ❌ no enum | (defer — clinical) | Defer to v1.5. |
+| 137 | QT interval | ms | ❌ no enum | (defer — clinical) | Defer to v1.5. |
+| 138 | Corrected QT (QTc) | ms | ❌ no enum | (defer — clinical) | Defer to v1.5. |
+| 139 | AFib classification result | enum | ❌ no enum | (defer — clinical event) | Defer to v1.5. |
+| 155 | Vascular Age | years | ❌ no enum | (new `VASCULAR_AGE`) | Body Scan. Defer to v1.4.26. |
+| 167 | Nerve Health Score | 0–100 | ❌ no enum | (new) | Body Comp / Body Scan, US-only via Total Biomarker Pack. Defer to v1.4.26 — niche. |
+| 168 | Extracellular Water | L | ❌ no enum | (new) | Body Scan exclusive. Defer to v1.5 — segmental composition is a sub-feature. |
+| 169 | Intracellular Water | L | ❌ no enum | (new) | Same. |
+| 170 | Visceral Fat | rating | ❌ no enum | (new `VISCERAL_FAT`) | Body Comp / Body Scan. Defer to v1.4.26. |
+| 174 | Fat Mass Segmental | kg per limb | ❌ no enum | (defer — JSON sub-doc) | Body Scan segmental. Defer to v1.5. |
+| 175 | Muscle Mass Segmental | kg per limb | ❌ no enum | (defer — JSON sub-doc) | Same. |
+| 196 | Electrodermal Activity | µS | ❌ no enum | (defer) | Nerve-health module. Defer to v1.5. |
+| 226 | Lean Mass | kg | ❌ no enum | (alias of 5?) | Same semantics as Fat Free Mass — Withings ships both; verify before mapping. Defer. |
+
+The `getmeas` call we already make sends `meastypes=1,6,9,10,11,54,77,88` (the keys of `MEASURE_TYPE_MAP`). To pick up the v1.4.25 additions we just extend the map; the query string grows automatically.
+
+**Unit semantics** — Withings encodes every value as `value * 10^unit` where `unit` is the decimal exponent (e.g. `value=65750, unit=-3` → `65.750 kg`). The existing client already does this `m.value * Math.pow(10, m.unit)`. No new conversion logic needed for v1.4.25 wires — all four additions are SI / dimensionless and inherit the exponent rule.
+
+**`category` parameter** — undocumented for new additions; we leave `category` unset, which returns *real measures* (not goals). No change needed.
+
+### 2.2 Sleep API — `POST /v2/sleep`
+
+Two actions: `get` (high-frequency series, ≤24h window) and `getsummary` (per-night aggregates).
+
+`getsummary` data fields (DB targets we'd need):
+
+| Field | Description | HealthLog target |
+|---|---|---|
+| `total_sleep_time` | Total sleep, sec | `SLEEP_DURATION` (minutes; convert) |
+| `total_timeinbed` | Total in bed, sec | sleepStage `IN_BED` row |
+| `asleepduration` | Total asleep, sec | sleepStage `ASLEEP` row |
+| `lightsleepduration` | Light sleep, sec | sleepStage `CORE` row (HealthKit names "Core" = light) |
+| `deepsleepduration` | Deep sleep, sec | sleepStage `DEEP` |
+| `remsleepduration` | REM, sec | sleepStage `REM` |
+| `wakeupduration` | Wake during night, sec | sleepStage `AWAKE` |
+| `wakeupcount` | Number of wake-ups | (no slot — defer) |
+| `durationtosleep` | Sleep latency, sec | (no slot — defer) |
+| `durationtowakeup` | Wakeup latency, sec | (no slot — defer) |
+| `sleep_score` | 0–100 | (no slot — surface in UI as raw or store as `WithingsSleepScore` later) |
+| `hr_average` / `hr_min` / `hr_max` | bpm | (no slot — defer) |
+| `rr_average` | breaths/min | (no slot — defer) |
+| `snoring` | sec | (no slot — defer) |
+| `breathing_disturbances_intensity` | severity 0–100 | (no slot — apnea screening signal; defer) |
+| `apnea_hypopnea_index` | events/h | (no slot — defer; clinical) |
+| `sdnn_1` (sleep block 1) | ms | `HEART_RATE_VARIABILITY` (per-night agg) |
+| `rmssd` | ms | (alternative HRV metric — store under same enum or add `RMSSD`?) |
+
+**v1.4.26 candidate.** Wiring this needs:
+1. A new sync routine `syncUserSleep(userId, opts)` that calls `POST /v2/sleep?action=getsummary`.
+2. `getmeas` and `getsummary` cannot share the same request because the two endpoints take different action verbs.
+3. Subscription `appli=44` (User Sleep) to drive webhook updates.
+4. Decide HRV storage: SDNN is what HealthKit + Apple Watch + Withings all expose, so map `sdnn_1` → `HEART_RATE_VARIABILITY` (existing enum). Skip `rmssd` for now.
+
+### 2.3 Heart API — `POST /v2/heart`
+
+Two actions: `list` (per-ECG-record metadata + AFib classification) and `get` (raw ECG signal in µV at 500 Hz).
+
+A `list` response item looks like:
+```json
+{
+  "ecg": { "signalid": 48, "afib": 1 },
+  "bloodpressure": { "diastole": 100, "systole": 101 },
+  "heart_rate": 82,
+  "timestamp": 1594159644
+}
+```
+
+- **`heart_rate`** field on a BPM Core record is already coverable via `getmeas` (meastype 11), so no new ingestion. But the `list` action gives us **AFib flag + ECG signal id + capture timestamp**, which `getmeas` does not. Defer to v1.5 with a `CardiacEvent` model. ECG signal storage is gigabyte-scale (500 Hz × 30s = 15k samples per capture); needs careful design.
+
+### 2.4 Activity / Workouts API — `POST /v2/measure`
+
+Three actions:
+
+| Action | Returns | Auth scope |
+|---|---|---|
+| `getactivity` | per-day aggregates: steps, distance (m), elevation, soft/moderate/intense sec, active sec, calories, totalcalories, hr_average/min/max, hr_zone_0..3 sec | `users.activity` |
+| `getintradayactivity` | high-freq per-minute samples of the same fields | `users.activity` |
+| `getworkouts` | discrete workout sessions with start/end + per-session aggregates + sport-specific fields (pool laps, strokes, GPS) | `users.activity` |
+
+**Mapping potential** (with `users.activity` scope added to OAuth):
+- `steps` → `ACTIVITY_STEPS` (enum exists; Apple Health path already uses it)
+- `distance` → `WALKING_RUNNING_DISTANCE` (enum exists)
+- `elevation` → `FLIGHTS_CLIMBED` (enum exists, but Withings unit is *floors*; verify — Withings docs list `elevation: Number of floors climbed`. Match!)
+- `calories` → `ACTIVE_ENERGY_BURNED` (enum exists)
+- `hr_average` per day → (no enum; could use `RESTING_HEART_RATE` if marked as "rest"; skip for now)
+
+**v1.4.26 candidate.** Wiring needs:
+1. Scope upgrade: append `users.activity` to `getAuthorizationUrl()` scope string. **Breaking change for existing connections** — they must reconnect. Mitigation: trigger reauth flow with messaging "we've added activity sync; reconnect to enable."
+2. New sync routine `syncUserActivity(userId)`.
+3. Workouts need a brand-new `Workout` model — defer that piece to v1.5.
+
+### 2.5 User API — `POST /v2/user`
+
+| Action | Returns |
+|---|---|
+| `getdevice` | List of user's devices: type, model, model_id, last activation, firmware version, battery |
+| `getbyuserid` | Internal user info (probably gated to dropshipment partners) |
+
+**v1.5 candidate.** A "Connected Withings devices" badge under Settings → Integrations is a nice polish item — surfaces which physical device the data came from. Not in v1.4.25 critical path.
+
+### 2.6 Notify API — `POST /notify`
+
+Subscribe / list / revoke / get. Subscribing requires the user's access token. The `appli` integer is the **category we want to be notified about**:
+
+| appli | Trigger | Scope | Service to call back |
+|---|---|---|---|
+| 1 | New weight/composition meas (types 1, 5, 6, 8, 88) | `user.metrics` | `Measure-Getmeas` |
+| 2 | New temperature meas (12, 71, 73) | `user.metrics` | `Measure-Getmeas` |
+| 4 | New BP/SpO2 meas (9, 10, 11, 54) | `user.metrics` | `Measure-Getmeas` |
+| 16 | New activity data | `users.activity` | `getactivity` / `getintraday` / `getworkouts` |
+| 44 | New sleep summary | `users.activity` | `Sleep v2-Get` / `Getsummary` |
+| 46 | User profile changed (delete / unlink / update) | `user.info` | (no fetch — react to event) |
+| 50 | Bed in event | `user.sleepevents` | (no fetch) |
+| 51 | Bed out event | `user.sleepevents` | (no fetch) |
+| 52 | Sleep sensor inflate done | `user.sleepevents` | (no fetch) |
+| 53 | No account associated (cellular device handoff) | n/a | `User v2-Link` |
+| 54 | New ECG data | `user.metrics` | `Heart v2-List` |
+| 55 | ECG measure failed | `user.metrics` | (no fetch) |
+| 58 | New glucose meas | `user.metrics` | `Measure-Getmeas` |
+| 119 | New glucose (alternate code per partner package) | `user.metrics` | `Measure-Getmeas` |
+
+**Gap:** HealthLog only subscribes to `appli=1`. **Even today**, BP readings (meastype 9/10/11) and SpO2 (54) flow in via the hourly poll, not via webhook — because they live behind `appli=4`, not `appli=1`. This is an **unflagged latency bug**: a new BP reading takes up to an hour to surface in HealthLog. Fix-in-v1.4.25 candidate (cheap; just subscribe to `appli=4` as well).
+
+For v1.4.25 we add `appli=2` (temperature) and `appli=4` (BP/SpO2) subscriptions to match what we already poll for. `appli=58` (glucose) we leave aside until we connect a Withings glucose device (none in BPM/scale family today — gated to CGM partners).
+
+### 2.7 Notes on Withings+ subscription
+
+None of the endpoints in §2.1 – §2.6 require a Withings+ subscription on the user's side. Coverage is purely a function of:
+1. **Withings developer app permissions** — set per-app in the partner hub.
+2. **OAuth scope** — must include `users.activity` / `user.sleepevents` / `user.info` for the corresponding endpoints.
+3. **Hardware** — the user needs the device that produces the metric (ScanWatch for SpO2, Body Scan for segmental composition, etc.).
+
+The Withings+ tier (`Cardio Check-Up`, `Health Improvement Score`, `Vitality Indicator`) sits **above** the API layer — those features are computed inside Withings' app and are not exposed by the public API. There's nothing to "ingest" from Withings+ even if the user pays. See `.planning/research/withings-plus-comparison.md` §1.2.
+
+**This is good news.** Marketing copy can honestly say: *"HealthLog reads everything a Withings device records, regardless of whether you subscribe to Withings+."*
+
+---
+
+## Section 3 — Gap scoring
+
+Scale: User-value (UV) 5=most users / 1=niche. Effort (E) 5=trivial / 1=multi-day. Schema-impact (S) 5=none / 1=new model needed.
+
+| Gap | UV | E | S | Wave | Rationale |
+|---|---|---|---|---|---|
+| meastype 12 Temperature (legacy) | 2 | 5 | 5 | **v1.4.25** | One line in `MEASURE_TYPE_MAP`. Enum already has `BODY_TEMPERATURE`. |
+| meastype 71 Body Temperature (Thermo) | 3 | 5 | 5 | **v1.4.25** | Same. Thermo owners get fever tracking sync. |
+| meastype 35 SpO2 (alt code) | 3 | 5 | 5 | **v1.4.25** | Same. Some devices report 35 instead of 54. |
+| meastype 123 VO2 max | 3 | 5 | 5 | **v1.4.25** | Same. Enum already has `VO2_MAX`. |
+| Subscribe appli=4 (BP webhook) | 5 | 5 | 5 | **v1.4.25** | Latency bug fix. BP currently waits an hour; should be seconds. |
+| Subscribe appli=2 (temperature webhook) | 2 | 5 | 5 | **v1.4.25** | Cheap; matches the new meastype 12/71 mapping. |
+| meastype 73 Skin Temperature | 2 | 4 | 3 | v1.4.26 | Needs new `SKIN_TEMPERATURE` enum (different physiology than core). |
+| meastype 5/8/76 Body composition (FFM / FM / Muscle) | 4 | 4 | 3 | v1.4.26 | Three new enum values + i18n strings + chart slots. Body Comp / Body Scan owners care. |
+| meastype 170 Visceral Fat | 3 | 4 | 3 | v1.4.26 | New enum slot. Body Comp / Body Scan. |
+| meastype 91 Pulse Wave Velocity | 3 | 4 | 3 | v1.4.26 | New enum slot. Body Cardio / Body Scan, EU+US only. |
+| meastype 155 Vascular Age | 2 | 4 | 3 | v1.4.26 | New enum slot. Composite of PWV + age — surfaces a "year" value. |
+| Sleep API (getsummary) — duration + stages + HRV | 5 | 3 | 4 | v1.4.26 | New sync routine; uses existing `SLEEP_DURATION`/`HEART_RATE_VARIABILITY` enums + `SleepStage`. Pairs with W4-shipped sleep chart. |
+| Activity API (getactivity) — steps + distance + calories | 4 | 3 | 5 | v1.4.26 | Existing enums; scope upgrade requires user reauth. |
+| Workouts API (getworkouts) | 3 | 2 | 1 | v1.5 | Needs `Workout` model with sport type + GPS + per-session aggregates. |
+| Intraday activity (getintradayactivity) | 2 | 3 | 4 | v1.5 | Per-minute samples; volume question (50k+ rows/day per user). Defer until storage strategy is set. |
+| ECG signal (Heart-Get) | 5 | 1 | 1 | v1.5 | 30s @ 500 Hz signals; needs blob storage strategy + cardiologist-disclaimer copy. Off-strategy for clinical interpretation. |
+| AFib events (Heart-List + appli=54) | 4 | 2 | 2 | v1.5 | Needs `CardiacEvent` model + alerting policy. Clinical surface — design care. |
+| meastype 167 Nerve Health Score | 1 | 4 | 3 | v1.5 | US-only via Total Biomarker Pack on Body Comp / Body Scan; niche. |
+| meastype 168/169 Extracellular / Intracellular Water | 2 | 4 | 3 | v1.5 | Body Scan exclusive; clinical-adjacent. |
+| meastype 174/175 Segmental composition (per-limb) | 2 | 3 | 1 | v1.5 | JSON sub-document; needs new column or sidecar table. |
+| meastype 196 Electrodermal Activity | 1 | 3 | 3 | v1.5 | Nerve-health module; niche. |
+| meastype 4 Height | 3 | 4 | 4 | v1.5 | Belongs on `User` profile, not as time-series. Wire to `User.heightCm` with last-write-wins. |
+| Devices list (User-Getdevice) | 3 | 4 | 5 | v1.5 | "Connected device" badge under Settings; needs a new API route + UI surface. |
+
+---
+
+## Section 4 — Webhook coverage
+
+Withings push (notify) covers every category in §2.6. HealthLog **today** only subscribes to `appli=1`, meaning:
+
+| Category | What it covers | HealthLog has webhook today? | Latency on a new reading |
+|---|---|---|---|
+| 1 — Weight/composition | meastypes 1, 5, 6, 8, 88 | ✅ yes | ~seconds |
+| 4 — BP & SpO2 | meastypes 9, 10, 11, 54 | ❌ no | up to 1 hour (poll) |
+| 2 — Temperature | meastypes 12, 71, 73 | ❌ no | up to 1 hour |
+| 44 — Sleep | sleep summary | ❌ no (not ingested at all) | n/a |
+| 16 — Activity | steps / distance / calories | ❌ no (not ingested at all) | n/a |
+| 54 — ECG | ECG records | ❌ no | n/a |
+| 58 — Glucose | meastype 119 | ❌ no | n/a |
+
+**Cadence reasonableness for poll-only fallback:**
+- Hourly poll for weight/BP/temperature is fine — those are spot readings made a few times per day.
+- For sleep, hourly poll is fine — there's one summary per night.
+- For activity, hourly poll would miss the live-step feedback loop entirely. **Activity ingest cannot rely on poll** — it requires webhook.
+
+**v1.4.25 action:** subscribe to `appli=2` and `appli=4` for instant BP / temperature deltas. Cheap. Atomic commit `feat(withings): subscribe to BP + temperature webhooks alongside weight`.
+
+**v1.4.26 action:** add `appli=44` (sleep) and `appli=16` (activity) when those sync routines land.
+
+---
+
+## Section 5 — OAuth scope + subscription tier
+
+| Scope | Endpoints | Status |
+|---|---|---|
+| `user.metrics` | Measure-Getmeas, Heart v2 (BP from cuffs, SpO2, ECG metadata) | ✅ already requested |
+| `users.activity` | Activity, Sleep | ❌ not requested. Needs scope-string update + user reauth on next connect. |
+| `user.info` | User v2 (devices, profile) | ❌ not requested. |
+| `user.sleepevents` | Bed-in / bed-out / inflate events | ❌ not requested. Niche — defer to v1.5. |
+
+**Withings+ subscription:** none of the endpoints listed above require Withings+ on the user side. The "Cardio Check-Up review" is the only Withings+-locked surface that exposes derived data, and it ships as a PDF to the user — there's no API for HealthLog to pull from.
+
+**Developer-app billing tier (partner hub):**
+- Basic Biomarker Pack: weight, body fat %, BMR, BP, pulse, SpO2 — covers everything we ingest today.
+- Total Biomarker Pack: adds PWV, nerve health, ECG signal, segmental composition. Required for v1.4.26+ work that touches PWV/NHS/segmental.
+
+For HealthLog self-hosters, the partner hub pack is what their **own Withings developer app** gets registered as — we don't pay anything centrally. Document this in the docs so a self-hoster who wants PWV knows to flip their app to Total Biomarker Pack.
+
+---
+
+## Section 6 — Files that need touching for v1.4.25
+
+| File | Change |
+|---|---|
+| `src/lib/withings/client.ts` | Extend `MEASURE_TYPE_MAP` with meastype 12, 35, 71, 123. |
+| `src/lib/withings/sync.ts` | Call `subscribeWebhook(token, url, 2)` and `subscribeWebhook(token, url, 4)` alongside the existing `appli=1`. |
+| `src/lib/withings/__tests__/client.test.ts` | **New file.** Cover the four new mappings + edge cases (unit exponent, missing fields, unknown meastype). |
+| `src/lib/withings/mapping.md` | **New file.** Single source-of-truth table of every meastype → MeasurementType. Reference from `client.ts` doc comment. |
+| `docs/api/openapi.yaml` | No change. Endpoint surface didn't change. |
+| `messages/en.json` + `messages/de.json` | No new user-facing keys needed for the meastype additions — the values surface in existing measurement charts via their already-localised types. |
+| `.planning/research/withings-api-coverage.md` | This file (delivered). |
+
+For v1.4.26 (NOT in this wave):
+- `prisma/schema.prisma` — add `FAT_MASS`, `FAT_FREE_MASS`, `MUSCLE_MASS`, `SKIN_TEMPERATURE`, `PULSE_WAVE_VELOCITY`, `VISCERAL_FAT`, `VASCULAR_AGE` to `MeasurementType` enum.
+- `prisma/migrations/0046_withings_body_composition_metrics/migration.sql` — additive enum values.
+- `src/lib/validations/measurement.ts` — extend `measurementTypeEnum`, `unitMap`, `VALUE_RANGES`.
+- `src/lib/withings/sleep.ts` — **new.** `Sleep v2-Getsummary` client + sync routine.
+- `src/lib/withings/activity.ts` — **new.** `Measure v2-Getactivity` client + sync routine.
+- OAuth scope string upgrade (`getAuthorizationUrl`): `"user.metrics,users.activity"`.
+
+---
+
+## Section 7 — Implementation plan for v1.4.25
+
+Per the wave brief, atomic commits per logical sub-change. Each test file lives under `src/lib/withings/__tests__/`.
+
+1. `chore(withings): document the full meastype mapping in src/lib/withings/mapping.md` — single source of truth so future additions don't drift.
+2. `feat(withings): ingest meastype 12 (legacy temperature) into BODY_TEMPERATURE` — one line in `MEASURE_TYPE_MAP` + test.
+3. `feat(withings): ingest meastype 71 (body temperature) into BODY_TEMPERATURE` — same shape.
+4. `feat(withings): ingest meastype 35 (legacy SpO2) into OXYGEN_SATURATION` — same shape.
+5. `feat(withings): ingest meastype 123 (VO2 max) into VO2_MAX` — same shape.
+6. `feat(withings): subscribe to BP + temperature webhooks alongside weight` — extend `setupWebhook` to subscribe to appli 1, 2, and 4. Removes the up-to-1h latency on BP readings, gives real-time temperature deltas to anyone using a Thermo.
+
+Each commit ships green tests (`pnpm test`, `pnpm typecheck`, `pnpm lint`).
+
+---
+
+## Section 8 — Deferred items + rationale
+
+### v1.4.26 (next maintenance wave)
+- **Body composition expansion (meastypes 5, 8, 76)** — `FAT_FREE_MASS`, `FAT_MASS`, `MUSCLE_MASS` enum values. Body Comp / Body Scan ships these on every step; not surfacing them feels under-built for Withings owners. Schema migration is purely additive (new enum values).
+- **Skin temperature (meastype 73)** — `SKIN_TEMPERATURE` enum. Distinct physiology from core body temp.
+- **Pulse wave velocity (meastype 91)** + **Vascular age (meastype 155)** — Body Cardio / Body Scan exclusive; defer until enum expansion lands.
+- **Visceral fat (meastype 170)** — same wave.
+- **Sleep v2 sync (Getsummary)** — duration into `SLEEP_DURATION` minutes, per-stage rows via `SleepStage`, `sdnn_1` into `HEART_RATE_VARIABILITY`. Pairs cleanly with W4-shipped sleep chart at `/insights/schlaf` which already renders `SleepStage` rows.
+- **Activity sync (Getactivity)** — steps + distance + calories into existing enums (`ACTIVITY_STEPS`, `WALKING_RUNNING_DISTANCE`, `ACTIVE_ENERGY_BURNED`, `FLIGHTS_CLIMBED`). Requires OAuth scope upgrade — every existing connection must reconnect once. Plan a one-time banner in Settings explaining the reconnect.
+- **Webhook subscriptions appli=16 (activity) and appli=44 (sleep)** — paired with the above sync routines.
+
+### v1.5 (paired with iOS app)
+- **ECG signal (Heart-Get)** — 30 s × 500 Hz blob per capture; needs storage strategy (signed-URL object store? Postgres `bytea`?), retention policy, and the "this is not a diagnosis" disclaimer copy reviewed by Marc before shipping.
+- **AFib events (Heart-List + appli=54)** — needs `CardiacEvent` model and an alerting policy. Clinical-adjacent: requires careful product copy to avoid "HealthLog detected AFib" → "Withings detected AFib, here's the record" framing.
+- **Workouts (Getworkouts)** — needs `Workout` model: sport type, start/end, distance, calories, GPS polyline. iOS app context first because workouts will round-trip through Apple Health and ordering matters.
+- **Intraday activity** — per-minute samples; storage/aggregation strategy needs analytics-side work before we ingest.
+- **Devices list (User-Getdevice)** — surfaced as a "Connected devices" badge under Settings → Integrations.
+- **Height (meastype 4)** — `User.heightCm` last-write-wins, not a `Measurement` row.
+- **Segmental composition (meastypes 174/175)** — JSON sub-document or per-limb measurement variant; decide once we have a Body Scan device in test.
+- **Nerve health (167) / Extracellular & Intracellular Water (168/169) / Electrodermal Activity (196)** — Body Scan-exclusive niche.
+
+### Skip with rationale
+- **Withings+ derived metrics (Health Improvement Score, Vitality Indicator, Cardio Check-Up cardiologist review)** — not exposed by the public API. Computed inside Withings' app, not reachable by any partner. Cross-reference `.planning/research/withings-plus-comparison.md` §6 — HealthLog's own AI surfaces (Health Score, Coach, briefing) are the answer here.
+- **Sleep events appli=50/51/52 (bed-in / bed-out / inflate)** — niche; only useful with a Withings Sleep Analyzer mat. Defer indefinitely; we'd surface them only if a user explicitly asks.
+
+---
+
+## Section 9 — Forward compatibility note
+
+The mapping table in `src/lib/withings/mapping.md` is intended as the single place to grep when Withings ships a new meastype. When the Health Mate app surfaces a new metric:
+
+1. Find the numeric meastype in Withings' developer guide (`developer.withings.com/developer-guide/v3/data-api/all-available-health-data`).
+2. Check if HealthLog's `MeasurementType` enum has a slot. If yes, one-line addition to `MEASURE_TYPE_MAP`. If no, additive migration first.
+3. Add a unit test fixture for the new meastype.
+4. Update `mapping.md`.
+
+Marketing-side: the docs site `features/integrations.mdx` carries a forward-compatibility note that points back to this audit. The audit is updated each marathon, so the docs always link the latest coverage.
+
+---
+
+## Sources
+
+- [Withings API Reference (developer.withings.com)](https://developer.withings.com/api-reference)
+- [Withings Developer Guide — Data API → All Available Health Data](https://developer.withings.com/developer-guide/v3/integration-guide/bulkship-sdk/data-api/all-available-health-data)
+- [Withings Developer Guide — Data API → Keep User Data Up To Date (notifications)](https://developer.withings.com/developer-guide/v3/integration-guide/advanced-research-api/data-api/keep-user-data-up-to-date)
+- [Withings API — Measure (getmeas)](https://developer.withings.com/api-reference#tag/measure)
+- [Withings API — Sleep (sleepv2-get / getsummary)](https://developer.withings.com/api-reference#tag/sleep)
+- [Withings API — Heart v2 (list / get)](https://developer.withings.com/api-reference#tag/heart)
+- [Withings API — Measure v2 (getactivity / getintradayactivity / getworkouts)](https://developer.withings.com/api-reference#tag/activity)
+- [Withings API — Notify (subscribe / list / revoke)](https://developer.withings.com/api-reference#tag/notify)
+- HealthLog: `src/lib/withings/{client.ts, sync.ts, credentials.ts}`
+- HealthLog: `prisma/schema.prisma` — `MeasurementType`, `MeasurementSource`, `SleepStage`
+- HealthLog: `.planning/research/withings-plus-comparison.md` — v1.4.24 Withings+ feature comparison
@@ -0,0 +1,90 @@
+# Withings meastype → HealthLog `MeasurementType` mapping
+
+Single source of truth for the `MEASURE_TYPE_MAP` table in `client.ts`. When
+Withings ships a new measurement type, look it up in the Withings developer
+guide ([Data API → All Available Health Data][1], [Measure-Getmeas][2]) and
+either extend `MEASURE_TYPE_MAP` here or add a new `MeasurementType` enum
+value via `prisma/schema.prisma` + a new migration.
+
+Audit + scoring of the full surface lives in
+[`.planning/research/withings-api-coverage.md`](../../../.planning/research/withings-api-coverage.md).
+
+## Ingested today (v1.4.25)
+
+| meastype | Withings name | DB enum | DB unit | Source devices |
+|---|---|---|---|---|
+| 1 | Weight | `WEIGHT` | kg | every Body / Body+ / Body Cardio / Body Comp / Body Scan |
+| 6 | Fat Ratio | `BODY_FAT` | % | Body+ family |
+| 9 | Diastolic BP | `BLOOD_PRESSURE_DIA` | mmHg | BPM Connect / Core / Vision |
+| 10 | Systolic BP | `BLOOD_PRESSURE_SYS` | mmHg | BPM Connect / Core / Vision |
+| 11 | Heart Pulse | `PULSE` | bpm | BPM cuffs + scales (standing HR) |
+| 12 | Temperature (legacy Thermo) | `BODY_TEMPERATURE` | celsius | first-gen Thermo (WBT01) |
+| 35 | SpO2 (alt code) | `OXYGEN_SATURATION` | % | older firmware reports 35 instead of 54 |
+| 54 | SpO2 | `OXYGEN_SATURATION` | % | ScanWatch / BPM Vision |
+| 71 | Body Temperature (core) | `BODY_TEMPERATURE` | celsius | current-gen Thermo |
+| 77 | Hydration / Water Mass | `TOTAL_BODY_WATER` | kg | Body Comp / Body Scan |
+| 88 | Bone Mass | `BONE_MASS` | kg | Body Comp / Body Scan |
+| 123 | VO2 max | `VO2_MAX` | mL/(kg·min) | ScanWatch family |
+
+### Unit handling
+
+Withings encodes every value as `value × 10^unit` where `unit` is the
+decimal exponent (e.g. `value: 65750, unit: -3` → `65.750 kg`). The client
+applies this rule once per measure in `fetchMeasurements()`. New mappings
+do not need their own conversion as long as the canonical DB unit matches
+Withings' SI default (kg, %, mmHg, bpm, °C, mL/(kg·min), …).
+
+### Webhook subscriptions (v1.4.25)
+
+`POST /notify?action=subscribe` with `appli`:
+
+- `appli=1` — weight + composition meastypes (1, 5, 6, 8, 88)
+- `appli=2` — temperature meastypes (12, 71, 73)
+- `appli=4` — pressure meastypes (9, 10, 11, 54)
+
+Without all three, BP and temperature readings flow only through the
+hourly poll fallback. v1.4.25 fixes this for BP and temperature; sleep
+(`appli=44`) and activity (`appli=16`) ship with the corresponding sync
+routines in v1.4.26.
+
+## Deferred — v1.4.26
+
+| meastype | Withings name | Why deferred |
+|---|---|---|
+| 5 | Fat Free Mass | needs new `FAT_FREE_MASS` enum |
+| 8 | Fat Mass Weight | needs new `FAT_MASS` enum |
+| 73 | Skin Temperature | distinct physiology from core; needs `SKIN_TEMPERATURE` enum |
+| 76 | Muscle Mass | needs new `MUSCLE_MASS` enum |
+| 91 | Pulse Wave Velocity | Body Cardio / Body Scan exclusive; new enum |
+| 155 | Vascular Age | new enum, composite-derived years |
+| 170 | Visceral Fat | new enum, rating |
+
+Plus the new sync routines:
+
+- **Sleep** (`POST /v2/sleep?action=getsummary`) → `SLEEP_DURATION`,
+  `HEART_RATE_VARIABILITY` (sdnn_1), per-stage rows via existing
+  `SleepStage` enum.
+- **Activity** (`POST /v2/measure?action=getactivity`) → `ACTIVITY_STEPS`,
+  `WALKING_RUNNING_DISTANCE`, `FLIGHTS_CLIMBED`, `ACTIVE_ENERGY_BURNED`.
+  **Requires OAuth scope upgrade** to `users.activity` — every existing
+  Withings connection has to reconnect once.
+
+## Deferred — v1.5 (with iOS app)
+
+ECG signal storage (`Heart v2-Get`), AFib events (`Heart v2-List` +
+`appli=54`), workouts (`getworkouts`, needs new `Workout` model),
+segmental composition (174/175), nerve health (167), extracellular /
+intracellular water (168/169), electrodermal activity (196), connected
+devices badge (`User v2-Getdevice`), and Height (4) into `User.heightCm`.
+
+## Skip with rationale
+
+- **Withings+ derived metrics** (Health Improvement Score, Vitality,
+  Cardio Check-Up review) — not exposed by the public API. HealthLog
+  computes its own Health Score / Coach / Briefing. See
+  `.planning/research/withings-plus-comparison.md` §6.
+- **Sleep events** `appli=50/51/52` (bed-in / bed-out / inflate) — niche
+  Sleep Analyzer mat events. No plan today.
+
+[1]: https://developer.withings.com/developer-guide/v3/integration-guide/bulkship-sdk/data-api/all-available-health-data
+[2]: https://developer.withings.com/api-reference#tag/measure