3L daily hydration

Daily water target = 35 ml × bodyweight kg, with a +500 ml bonus on training days. The default for an 80 kg user is 2.8L non-training / 3.3L training. The 3L label is the round-number anchor — actual targets adjust to bodyweight at activation.

The target is split into four time buckets:

• Wake → noon: 25% of target
• Noon → 5pm: 30%
• 5pm → 8pm: 30%
• 8pm → bedtime: 15%

This back-loads the day toward training (5-8pm bucket is where most evening lifters drink), and tapers in the final hours so the user doesn't get up four times overnight.

Decision rules for the coach

• One card per day, four sub-targets. The daily hydration card splits into four bucket targets. Each bucket has its own tick.
• Auto-add 500ml on training days. When today's grid has a workout card, the resolver adds 500ml to the daily target, distributed proportionally across the bucket targets.
• No nag for misses. Hydration moralizing fails. Surface the current state if asked. Don't push.
• Caffeine and electrolytes don't substitute. If the user asks whether coffee / sports drink counts: yes, water content counts toward the target. Caffeine doesn't dehydrate the way the myth claims. Electrolyte drinks are useful but optional.
• Three-day trend. If logged intake is < 60% of target for three days running, surface it once. Then drop it.
• Adjustment. If the user is consistently over target without effort, no action — there's no downside to mild over-hydration in a healthy person. If under target for 4 weeks, suggest lowering the target by 250 ml — sustained achievable beats ambitious abandoned.
• Inline caveats. Hydration is medical-adjacent for users on certain medications or with kidney conditions — emit the caveat per respond-to-medical if the user mentions either context.