Your personal model of links
Everyone has their own patterns. Late coffee doesn't bother some people and costs others half an hour of sleep. So Pulse builds its model of links from your history only: signals (sleep, heart rate, energy, mood), behavior (habits, workouts, screen time), context (weather, weekday, cycle phase) and the suggestions you've tried.
A link isn't just "A and B happened together". It has a direction, a delay ("next day"), a strength in your own numbers and a confidence level. Links can form short chains: "late dinner → shorter sleep → lower energy the next day".
How Pulse finds links
We compare days "with" and "without": with a habit and without it, with a workout and without one. We check what comes first: a link that holds even after accounting for the previous day's state is more honest than a one-day coincidence.
We look for turning points ("since September 12 you've slept 40 minutes less — what changed then?") and thresholds ("from 2 cups of coffee on"). Links are built by statistics, not by a language model: the assistant only explains them in plain words.
How we filter out what's false
Compare hundreds of signal pairs and chance matches will always turn up. So Pulse tests every link against chance and corrects for how many comparisons it makes.
We account for the weekday, weather, cycle phase and slow trends. We drop atypical days — illness, travel. We check that a link doesn't rest on one or two days and that it repeats in both halves of your history. And we catch "just bad days": if the days without a workout were hard for other reasons, Pulse says so — "looks like it's not the workout".
Link strength — in your own numbers
No mysterious percentages or coefficients. Pulse shows a link so you can check it at a glance: "64 vs 51 out of 100 on average · over 24 days", with a delay ("next day") and a threshold ("from 2 cups on").
Every link has a level: "Solid", "Likely" or "Emerging". If a link hasn't been confirmed for a while, its confidence gradually fades. If there isn't enough data yet, Pulse says so honestly: "no links yet".
You're in the loop
You can answer "Is this you?" on every link. "Yes" — and it stands out more. Two "no"s — and Pulse removes it.
You can write down what you expect from a habit — Pulse checks it against days with and without it and shows whether the expectation holds. And everything Pulse remembers about you is on one screen: correct it or make it forget.
Every answer changes the next step
A typical tracker knows two states: done or not done. Pulse asks what got in the way: no time, no energy, circumstances changed, external constraints, no longer relevant, forgot. A deliberate day off doesn't break a habit streak. And if a reason keeps repeating, Pulse adjusts the next step: "forgot" — a different reminder time, "no energy" — a smaller step, a task that's "too big" — broken into steps.
Same with suggestions: decline one and explain in a tap ("too generic", "already knew this"), and Pulse won't repeat it. Energy check-ins refine your daily curve; the notifications you open tune when they arrive.
Step of the week: test it on yourself
The closest thing to answering "what actually helps me" is to try it. Step of the week is a small experiment: you pick one step, and after a week Pulse compares the result with your usual four weeks and suggests keeping, extending or dropping it. What you keep becomes a habit. Step of the week is part of Premium.
What we don't claim
Pulse doesn't diagnose and doesn't call a coincidence a cause. We say "linked to", not "causes" — and show how strong the link is and how to test it.
Links appear once there's enough data. In the first weeks, "no links yet" is normal: an empty model is more honest than a made-up one.
What's in each plan
Free — your top link in "What affects you" and every feedback loop. Pro — your top 5 links and a score breakdown by factor. Premium — every link, score forecasts and Step of the week. 14 days of Premium free, no card.