Garmin Nutrition Coach

<p align="center"> <img src="assets/leanloop-cover.jpg" alt="LeanLoop for Garmin — private AI nutrition & fitness coach (Garmin + Claude + Notion + Google Cloud)" width="100%"> </p>

Turn Claude into your personal, data-driven health coach — self-hosted, private, ~$0/month.

Your own MCP server connects Claude to your Garmin wearable data (14 lean tools) and your Notion workspace. A nightly job writes your real measured calorie burn into your food log — so your deficit numbers come from your body, not from generic formulas — and a built-in calibration loop checks them against your actual scale weight every two weeks.

Chat with Claude like a coach who has actually seen your data: "How did I sleep?" · "Coach me today" · "Why did my run feel bad?" · 📸 [photo of lunch]

✨ Features

	Feature	What it does
📸	Photo food logging	Send a meal photo → macros estimated with a documented protocol (reference-object scaling, hidden oil/sauce accounting) → auto-saved to Notion
🌙	Automatic day close	Every night your server pulls the finished day's true TDEE from Garmin and writes TDEE + workouts into your log (your deficit column recalculates itself instantly — it's a Notion formula) — self-heals 3 days back, colored sync tags show status at a glance
🔥	Progress you can see	Cumulative deficit (≈ kg of fat) updated nightly right on your Notion food log
🏃	Coaching on real data	One-call readiness verdicts, post-workout analysis (splits, HR zones, sleep context), weekly reviews, injury pattern tracking
📈	Second-by-second analysis	FIT-file parsing: HR/pace/cadence streams + aerobic decoupling — the endurance metric real coaches use
⚖️	Calibration loop	Every 2 weeks: logged deficit vs. actual weight change reveals your personal estimation bias, which corrects all future estimates
🔄	Live-updating brain	Coaching rules live in playbook.md, fetched by your server at runtime — improvements reach every user instantly, no reinstall

🚀 Install (no coding needed)

Open Claude and paste:

Read https://github.com/bank3005-jpg/LeanLoop-for-Garmin/blob/stable/SETUP.md and set this up for me

Claude interviews you (goals, body stats), creates your Notion databases, walks you through the cloud steps, and wires everything into a Claude Project — a dedicated space where your coach lives, with your server and Notion connected and your coaching rules loaded automatically in every chat. 45–60 minutes, one time.

Prerequisites: a Garmin watch · Notion account (free) · Google account with billing enabled (stays within free tier) · Claude plan with custom connectors · Windows or macOS computer for one step.

🏗️ Architecture

Claude (any device, incl. phone)
   └── your Cloud Run server  ← this repo, deployed to YOUR Google account
         ├── Garmin Connect   ← your token, created on your own computer
         ├── your Notion      ← food / training / body logs
         └── playbook.md      ← coaching rules, served live from GitHub
   Cloud Scheduler → nightly close-day job + keep-warm pings

Privacy by design: everything runs in your accounts. No third party — including this repo's author — ever sees your data. The server is protected by a long random secret; Garmin credentials never pass through chat.

🧰 What's inside (14 lean MCP tools)

Health get_wellness(metric) — sleep, HRV, stress, body battery, heart rate, SpO2, respiration, intensity minutes, hydration, blood pressure, body composition, training readiness/status · get_daily_summary Training get_activities (recent or date range) · get_activity(id, view) — summary, splits, HR zones, FIT streams, aerobic decoupling · get_fitness(metric) — VO2max, race predictions, endurance/hill scores, lactate threshold, PRs, fitness age · get_coach_snapshot (one-call verdict data) · analyze_activity (one-call post-workout bundle) · weekly_report / calibrate_report (pre-computed reviews) Body get_weight_history · add_body_composition (write InBody/DEXA scans into Garmin) System foodlog_read / foodlog_upsert (direct Notion food log) · get_playbook (live coaching rules)

Few tools by design: a lean tool list keeps every chat's context small — grouped tools with a metric/view parameter carry the same 35 capabilities at ~half the token overhead.

🔄 Updating

• Coaching rules — update automatically (served live from this repo)
• Server code — git pull + one deploy command, or enable a Cloud Build trigger on stable for fully automatic deploys
• Want to customize the code? Fork the repo and point your deployment at your fork

❓ FAQ

Is it really free? Yes — Cloud Run free tier covers personal use many times over. The setup guide includes guardrails so you stay in it. Does my data go anywhere? No. Your server, your Garmin token, your Notion. Self-hosted means self-owned. What if Garmin changes their API? The community library this builds on (python-garminconnect) gets patched quickly; update with one git pull + deploy. Garmin China accounts? Not supported (separate system). No watch some days? The nightly job falls back to your formula baseline and tags the day estimated.

💬 Why this exists

I'm not a programmer. I built LeanLoop together with Claude because I wanted to lose weight, get my confidence back, and just feel better — and I couldn't find a tracker that coached me on my real data instead of generic formulas. It worked for me, so I'm sharing it.

I use LeanLoop every single day and keep refining it as I go. If you hit a problem or want a feature, open a thread in Discussions — I read everything.

🙏 Credits

Built on python-garminconnect by cyberjunky · fitdecode · MCP by Anthropic.

⚠️ Disclaimer

This is a personal tracking and coaching tool, not medical advice or a medical device. Calorie and macro estimates are approximations. Consult a healthcare professional for medical decisions, and stop training and seek care for any concerning symptoms.

📄 License

MIT — use it, fork it, share it.