Kai · Muse
Cycle, mood, body rhythm

Your cycle,engineered.

Muse logs the cycle and reads it everywhere else. Phase, mood, and body rhythm are captured once, then quietly shifted into Lift's volume, Fuel's macros, Ease's recovery target, and Moment's reflection.

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Cycle · August
Day 23Late luteal
Day
23
Luteal -5 d
Calendar
28 days
MenstrualFollicularFertile estimateLuteal
Insight · today
Read by 4 apps
Late luteal, low energy noted. Lift volume is capped at maintenance. Fuel tilts toward iron and carbs.
Two modes

Tracked by you. Read by Kai.

Both modes write to the same calendar, insights, and shared context. Switch any time, even mid-cycle.

Mode 01
Previewing

Agent check-ins

Muse picks a moment in your day to ask the one question it actually needs, builds the calendar from your answers, and writes reminders that fit your reminder policy.

  • One question, picked from this week's signal
  • Auto-built calendar from start and end logs
  • Reminders that respect your policy
  • Insights row updated nightly
Check-in · Tue 9:14 PM
Adaptive

Two days into a longer luteal than last month. Energy lower than usual?

Reminder · 9 PMSave
Mode 02

Manual logging

When you want the pen. Save daily flow, symptoms, mood, and energy directly. Keep period predictions and conception-awareness estimates grounded without an agent in the loop.

  • Daily cycle check-ins
  • Saved cycle check-ins on a tap
  • Calendar view with contracted fertility estimates
  • Insights you can read or hide
Period · August
Manual
Start periodAug 02
End periodAug 06
Update length29 days
Saved check-ins · cramp 1-3 · headache 1 · steady
A real cycle slice

Calendar, insight, and one cross-domain effect.

Day 23, late luteal. A saved check-in flags low energy. Lift drops a working set. Fuel tilts toward iron and carbs. Nothing here asked you to ask.

Tuesday · Aug 22
/
Cycle day 23
/
Late luteal
Calendar
28-day view
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
MenstrualFollicularFertile estimateLuteal
Insights row
Tonight
  • Phase-5 days to start
    Luteal · day 23 of 28
  • Symptom loadSaved check-in · 9:14 PM
    Low energy · cramp 1
  • Sleep needTrend · last 3 luteals
    +22 min vs baseline
  • PeriodReminder · 2 days out
    Predicted Mon, Aug 28
Felt elsewhere
Auto
  • Lift
    Working-set volume capped at maintenance: squat 3x5 instead of 5x5.
  • Fuel
    Macros tilted: +18 g iron-rich protein, +35 g carbs in dinner.
  • Ease
    Recovery target softened. The rest day stays protected for Thursday.
Each app read the phase and adjusted without asking for a duplicate log.
Signal, not noise

The cycle, read clearly, and only what matters.

Phase length, symptom load, and the correlations actually worth surfacing. No daily horoscope. No prediction theatre.

  • Cycle length across the last 6 cycles, with variance flagged
  • Symptom load by phase, not by isolated day
  • Correlations with Lift load and Pace volume
  • Predictions hidden unless asked
No streak shame

Late by a day? The calendar shifts. Phase is biology, not a habit.

Cycle length · last 6
28.3avg days · sigma 1.2
Mar-Aug
27
29
28
30
28
27
Symptoms by phase
  • Menstrual
    85
  • Follicular
    20
  • Fertile estimate
    35
  • Luteal
    62
Correlation
Pace volume drops 14% in luteal, and your reported RPE does not. That is not training error.
Read from Pace
Kai across your domains

Cycle phase is the rare signal that should change everything.

Through the user context bridge, every other Kai agent reads the current phase before it writes a recommendation. Four examples, one per class.

user context · phase = luteal · day = 23
  • Class 01 · Training + Nutrition
    LiftFuel
    Trigger · in Muse

    A logged late-luteal phase

    Effect · elsewhere

    Lift drops working-set volume a notch. Fuel tilts the day toward higher iron and an extra serving of carbs.

  • Class 02 · Recovery
    Ease
    Trigger · in Muse

    An Ease recovery dip lined up with cycle phase

    Effect · elsewhere

    Kai protects the rest day instead of writing an adherence scold. Readiness is compared against context.

  • Class 03 · Reflection
    Moment
    Trigger · in Muse

    A mood check-in saved on day 23

    Effect · elsewhere

    A later reflection can say this week echoes last cycle's late luteal pattern instead of filing the note away.

  • Class 04 · Reflection + Cardio
    MomentPace
    Trigger · in Muse

    A stretch of low-energy runs in Pace

    Effect · elsewhere

    Post ties the dip to cycle phase rather than training error. Pace does not get blamed for biology.

One signal, four classes.

Cycle phase touches training, nutrition, recovery, and reflection at once. Muse is the only place that needs to know it.

One coach, six domains

Muse is one part of Kai.

Each Kai sub-app focuses on one thing and does it precisely. Muse tracks the cycle so Lift, Fuel, and Pace can prescribe around it, not at it.

One subscription. Six apps. Shared context.

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