Read this first when you need to interpret local times or address the
    athlete by name.
    

    Read this before judging whether a session was easy or hard; zone
    boundaries differ per sport.
    

    Defaults to the last 30 days. Filter by activity_type such as Run,
    TrailRun, Ride, Swim, Hike, Workout, WeightTraining, Yoga. Each entry
    carries distance, duration, pace, heart rate, elevation, training load
    and the CTL/ATL standing at the time. The response reports how many
    activities matched versus how many were returned.
    

    Use it when you already have an id (from list_activities, an event,
    or the athlete) and want that one activity without re-listing a whole
    window. It does not currently surface fields list_activities omits.
    

    Use it to see how a session was structured: per-lap distance, duration,
    pace, heart rate, power and zone. This is where interval execution shows
    up, such as whether reps faded.
    

    types is a comma-separated list, for example heartrate, velocity_smooth,
    altitude, cadence, watts, temp, latlng. Returns `points` evenly spaced
    samples per series plus min/mean/max over the whole series. points must
    be between 2 and 2000. The raw data can exceed ten thousand samples per
    series, so pass full=true only when the shape of every second genuinely
    matters -- not a small `points` value, which is rejected rather than
    silently answered with the full series.

    latlng sometimes comes back from intervals.icu as latitude only rather
    than [lat, lon] pairs; when that happens the series carries a note
    saying so instead of a silently wrong coordinate.
    

    Defaults to the last 30 days. Per day: CTL (fitness), ATL (fatigue),
    ramp rate, plus whatever the athlete logs — weight, resting HR, HRV,
    sleep, soreness, fatigue, stress, mood, motivation. This is the record
    to read before judging whether load is sustainable.
    

    Defaults to a six-week window so recent HRV has a real baseline to
    compare against. Returns TSB (fitness minus fatigue) classified into a
    band -- high_risk, overreaching, neutral, fresh, very_fresh -- each
    with a plain-language note, plus a ramp-rate read (declining,
    maintaining, building, aggressive) and, when HRV is logged, the last
    7 days against the rest of the window with a flag if it has dropped
    more than 10% below baseline.
    

    Defaults to today through 28 days ahead. Pass an earlier oldest to see
    what was planned in the past. An empty list means nothing is scheduled.
    

    kind is hr, pace or power. Returns the best value held for 5s, 15s, 30s,
    1m, 5m, 10m, 20m, 30m, 1h and 1h30m over the window, which defaults to
    the last 12 months. Use it to compare current form against past peaks.
    

    kind is hr, pace or power, same as get_best_efforts. Use this when the
    shape of the curve -- a plateau, a cliff past some duration -- says
    more than the ten named points get_best_efforts returns.
    

    These are workout templates, not completed sessions; use list_activities
    for what was actually done.
    

    Use only when a dedicated tool cannot answer the question, since raw
    payloads are large. path is relative to https://intervals.icu/api/v1,
    for example "athlete/{athlete}/activities"; "{athlete}" expands to the
    configured athlete id. Pass query arguments in params, not in the path.
    This is still read-only.

    Field names are returned as-is, but values that look like credentials
    or personal contact info -- email, API keys, tokens, invitation links
    -- are replaced with "[redacted]" wherever they appear in the payload.