Health check: data source, how many metrics/workouts are available, and the most recent data date. Call this first to confirm the bridge is connected.

List every available Apple Health metric with its unit, day count, and date range. Use this to discover metric names before querying.

Get values for a metric (or all metrics) over an optional date range, with an aggregate (avg/sum/min/max/latest). The core data-retrieval tool. Every result carries a coverage block giving the metric's real firstDate/lastDate/days — check it before trusting a long window, and note that aggregate is always computed over the full range even when points are rolled up.

Compare the most recent N-day window against the prior N days for a metric — returns change, percent change and direction (up/down/flat). Also returns daysAvailable and windowSatisfied: if windowSatisfied is false the file does not hold enough history for the window you asked for, and the comparison is over less data than requested.

Compare a metric between two arbitrary date periods (A vs B) — returns each aggregate plus the change and percent change.

Return clean structured JSON for the chosen metrics/date range. Paginated: the result carries nextCursor when more metrics remain — pass it back as cursor for the next page. Prefer naming the metrics you need and a date range; calling it bare over a full history is a lot of data.

Natural-language convenience: pass a question and get routed structured results. Prefer the specific tools above when you can — and call list_metrics first to see how much history exists, since this tool answers over whatever the file holds.