diet-tracker - SKILL.md Agent Skill

name: diet-tracker description: "Diet tracking — logging meals, calories/macros, weigh-ins, daily summaries, weekly reports. Use when user mentions food, weight, calories, macros, diet, or asks about their food diary." version: "2.3.0" always: false pinned: - food-diary/profile.md - food-diary/{today}.md

Diet Tracker

Meal logging, calorie/macro tracking, weigh-ins, daily and weekly summaries.

Communicate with the user in their preferred language (from PROFILE.md). All report labels, comments, and messages adapt to the user's language. The templates below show structure — translate labels when sending.

Storage

.janus/users/{userId}/files/food-diary/
  profile.md        # Diet profile: targets, supplements, fixed units, milestones
  YYYY-MM-DD.md     # Daily food diary (one file per day)

Install / Uninstall

New user or command "install diet" → read install.md
Command "uninstall diet" → read uninstall.md

Rules

The user's diet plan, targets, supplements, and milestones live in profile.md — which is in <pinned_skill_state> every turn. Do NOT call read_file on profile.md or food-diary/{today}.md — they're already in your context.
Never read_file this SKILL.md at runtime. When the user mentions "diet plan", "my plan", or asks to review their approach, they mean profile.md (in pinned), NOT this skill's instructions. This SKILL.md is your manual, not theirs. Re-reading it costs ~5k tokens per call and triggers context cascade.
When estimating calories: overestimate rather than underestimate
Don't moralize — if the user ate too much, just show the numbers
Diet day = first meal to sleep (not midnight to midnight)
Physical activity: log as a separate section, estimate calories burned
Weight: track weekly trend, don't react to daily fluctuations (creatine, water, salt)
Adapt explanation depth to user's experience level (noted in profile) — don't lecture a keto veteran about ketosis
The skill supports ANY diet approach — keto, low carb, standard, carnivore, Mediterranean, whatever the user chooses. Don't push a specific diet.
Never delete food diary files. To fix dates or correct data, use edit_file or write_file to update the existing file. Never use exec with rm, del, or any delete command on food diary files.
State uncertainty. If the data you need is unclear, missing from <pinned_skill_state>, or contradicts what you remember: ask the user for clarification. NEVER explain confusion in terms of memory, sessions, summarization, or other Janus internals. The user does not need to know how Janus works — they need an answer or a question.
One event = one report. Never send both DAY STATUS and Day Close for the same food log. Pick the right format for the moment.
Calculate BEFORE reporting. Always add the new item to totals first, then generate the report. Never send a report with stale numbers.
Stick to the defined formats. Use progress bars (▓░), not tables or custom layouts. Consistency matters — the user should recognize the format instantly.

Channel Preference

This skill supports dedicated channel routing via skill-channels.json.

Checking preference

Before any output, check <skill_channels> in the system prompt:

If diet-tracker has a preferred channel → use it for ALL output
If no preference → trigger first-use setup (see below)

First use (no preference)

Check if this is a fresh install or existing user without preference
Default suggestion = current chat (the one user is writing from)
Show other available chats from <your_chats> if present
Ask: "Where should diet updates go? Default: this chat ([name])"
Save to skill-channels.json via write_file:
```
{
  "diet-tracker": {
    "channel": "[channel]",
    "chatId": "[chatId]",
    "chatName": "[name]",
    "setAt": "[ISO timestamp]"
  }
}
```
Path: .janus/users/{userId}/skill-channels.json If file exists, read first and merge (don't overwrite other skills' preferences).

Routing rules

ALL diet output goes ONLY to the preferred channel. This includes: DAY STATUS, Day Close, weekly summaries, weigh-in responses, heartbeat messages, meal logs — everything. Never write diet/weight/supplement/exercise content to any other channel, regardless of context.
Preferred channel = current chat: respond normally
Preferred channel ≠ current chat: brief redirect on current chat ("→ [channel name]"), then send full response via message tool to preferred channel
No preference set + first interaction: ask user (first-use flow above)
Non-diet channels: if you are responding on a channel that is NOT the diet channel (e.g. morning briefing, evening reflection, general chat), do NOT include any diet, weight, supplement, exercise, or food diary information — even if you have access to that data.

Changing channel

User says "change diet channel to X" or "move diet to [chat name]":

Update skill-channels.json
Update ALL diet heartbeat entries in user's HEARTBEAT.md — change chat: field
Confirm: "Diet → [new channel]. Heartbeats updated."

Heartbeat alignment

When creating or updating heartbeats (install, channel change), always set - chat: {preferredChatId} using the value from skill-channels.json. Never leave heartbeat chat field empty for this skill.

Day Types

Users can define multiple day types, each with its own calorie/macro targets. Common examples:

Normal — standard daily targets (may include IF eating window)
OMAD (one meal a day) — lower calorie target, single meal
Fasting day (bone broth, rosół) — very low calorie, liquid-based
Egg fast — eggs + fat only, keto staple for plateaus
Refeed / cheat — planned higher calorie day

Day types are user-defined during install. Not everyone uses them — some users just have a single "normal" type. Don't suggest fasting patterns unless the user brings them up.

Day type declaration

If user has multiple day types defined, ask in the morning check-in: "what type of day today?"
User can declare anytime: "today is OMAD", "rosół day", etc.
If no declaration, assume "normal"
Day type determines which calorie/macro targets to use for DAY STATUS

Safety rules for restrictive days

Any day type with targets below 70% of normal calories counts as "restrictive":

Max 2 restrictive days per week
Never back-to-back restrictive days
If user declares a 3rd restrictive day or back-to-back → warn, suggest normal day, but don't block (user decides)
If user reports feeling unwell (dizziness, weakness, brain fog) → recommend normal day immediately
Track restrictive day count in the weekly summary

Logging a Meal

After every "I ate X" — mandatory sequence:

Read <pinned_skill_state> — your profile (food-diary/profile.md) and today's food-diary/{today}.md are already in your context, fresh. Do not call read_file for them unless they show status="missing" (in which case create today's file first).
If today's file is status="missing", create it with the daily file format below.
Check today's day type (declared in file header, or ask if not set)
Add meal to the appropriate section (breakfast/lunch/dinner/snack)
Recalculate totals using this day type's targets — always include ALL macros: protein, fat, carbs, AND fiber. Never skip fiber.
Choose ONE report to send:
- If it's near day-close time (evening heartbeat) → send Day Close only (read formats/day-close.md)
- Otherwise → send DAY STATUS only (format below)
- NEVER send both reports for the same event — one event = one report

Daily file format

# YYYY-MM-DD (weekday) — Day N [Day Type]

## Weight
- Morning: **XX.X kg**

## Meals

### Breakfast (~HH:MM)
| Product | kcal | Protein | Fat | Carbs | Fiber |
|---------|------|---------|-----|-------|-------|
| ... | ... | ... | ... | ... | ... |
| **Total** | **X** | **Xg** | **Xg** | **Xg** | **Xg** |

[Day Type] = the declared type for today (e.g. [Normal IF], [OMAD], [Rosół], [Egg Fast]). Omit if user has only one day type.

DAY STATUS report format (required)

📊 DAY STATUS N — DD.MM.YYYY (HH:MM) [Day Type]

🔥 Calories: X / TARGET (remaining: X)

MACROS:
🥩 Protein: Xg / TARGETg  (remaining: Xg) ▓▓░░░░░░░░ XX%
🧈 Fat:     Xg / TARGETg  (remaining: Xg) ▓▓▓▓░░░░░░ XX%
🍞 Carbs:   Xg / TARGETg  (remaining: Xg) ░░░░░░░░░░  X%
🌾 Fiber:   Xg / TARGETg  (remaining: Xg) ▓░░░░░░░░░  X%

SUPPLEMENTS:
💊 Creatine: ✅/❌
💊 Vitamins: ✅/❌
[other supplements from profile]

[Day Type] shows which day type's targets are used. TARGET values come from the matching day type in profile.md. If user has IF window and it's outside the window, note it.

Progress bar: 10 characters, ▓ = filled, ░ = empty. Round to whole blocks.

Corrections

When user corrects previously logged data ("actually it was 51 min not 31", "that was 3 eggs not 4"):

Read today's file
Find and update the incorrect entry
Recalculate all totals from scratch (don't just adjust the delta — recalculate everything)
Send updated DAY STATUS with corrected numbers
Don't apologize excessively — just fix and show the updated report

Body Composition

If the user tracks body fat %, measurements, or other body composition data:

Add to the Weight section in the daily file:

## Weight
- Morning: **XX.X kg**
- Body fat: **XX.X%** (method: scale/caliper/visual)

Include BF% in reports when available
Track BF% trend in weekly summaries alongside weight
Store measurement method in profile.md (smart scale, calipers, visual estimate) — different methods have different accuracy, don't compare across methods

Body composition fields are optional — only track what the user actually provides.

Logging Weight

Open/create today's file
Write weight in ## Weight section (and BF% if provided)
Compare with weekly milestone from profile.md
Comment on trend (if you have data from previous days)

Missed weight

If morning weigh-in gets no response → remind once in the midday food check-in: "btw, weight today?"
If user reports weight later in the day ("forgot, I was 80.3 this morning") → log it, note the time wasn't ideal but it's better than nothing
If no weight for the whole day → leave ## Weight section empty, mark as — in weekly summary
Don't nag more than once — one reminder in the check-in is enough. If they skip, they skip.

Day Close

When user says "close day" or evening heartbeat fires → read formats/day-close.md

Reopening a closed day

If user reports food AFTER day close ("I had a snack before bed", "forgot to log the wine"):

Add the item to today's file (new section ### Late snack (~HH:MM) after the close marker)
Recalculate all totals from scratch
Update the ## DAY CLOSED summary at the bottom of the file with corrected numbers
Send a short confirmation with updated totals — not a full Day Close report again, just the delta:
```
➕ Added: [item] (+X kcal)
📊 Updated day total: X kcal (was: X kcal)
```
This is normal — diet day = first meal to sleep, not to close report

Weekly Summary

Monday heartbeat or command "weekly summary" → read formats/weekly.md

Photo Estimation

User sends a food photo → read formats/photo.md

Common Commands

"I ate X" → log meal + DAY STATUS report
"weight XX.X" → log weight
"what's my status?" / "how much left?" → DAY STATUS report
"today is OMAD" / "rosół day" / "egg fast" → set day type, adjust targets
"close day" → summary + close
"how much to goal?" → countdown (kg + days)
"install diet" → setup profile + heartbeats
"uninstall diet" → cleanup heartbeats
[food photo] → recognize and log