Nutrition MCP

A remote MCP server for personal nutrition tracking — log meals with calories, macros, fiber and total sugar, log water and body weight, review nutrition history, and import an existing food diary from another app, all through conversation. Alcohol tracking is opt-in and off by default.

Help me pay for the servers on Patreon

Quick Start

The current runtime is a single-user, no-auth Bun server backed by local PostgreSQL. It exposes the MCP protocol at POST /mcp; there is no Supabase, OAuth, email/password, or account-registration step.

bun install
cp .env.example .env
# Ensure PostgreSQL is running and DATABASE_URL points at the database to use.
bun run start

Then configure an MCP client with http://localhost:8080/mcp. The hosted URL https://nutrition-mcp.com/mcp is a deployment-specific endpoint, not a different authentication flow.

Switching from another tracker? See the nutrition-app alternatives — how it compares to MyFitnessPal, Cronometer, Lose It!, MacroFactor, Yazio, and Lifesum. Bring your history with you: say "import my meals" and an importer opens in the chat, where you pick the CSV you exported from your old app, map its columns, and check what will be added before anything is saved. Exports from MyFitnessPal, Cronometer, Lose It! and MacroFactor are recognised automatically; any other CSV works by mapping its columns yourself. In clients that can't show in-chat panels, paste the export instead and the AI imports it for you. If your export has an alcohol column and you want it kept, turn alcohol tracking on before importing — the importer skips that column while tracking is off, and re-importing the same file later won't backfill it.

Related MCP server: nutrition-mcp

Demo

Read the story behind it: How I Replaced MyFitnessPal and Other Apps with a Single MCP Server

Tech Stack

• Bun — runtime and package manager

• Hono — HTTP framework

• MCP SDK — Model Context Protocol over Streamable HTTP

• PostgreSQL — local database, configured with DATABASE_URL

• No authentication — this runtime is single-user and exposes /mcp directly

MCP Tools

Food-tracking storage and scope

Food tracking uses an append-only meal_events aggregate: each correction creates a new version and advances the root pointer; historical versions and evidence remain readable. The legacy meal tables are reset destructively by migration 002 when it is applied, so take an export before upgrading. Event media bytes live under MEDIA_ROOT; PostgreSQL stores only the generated event/version/content-hash key and metadata. DATABASE_URL_TEST points integration tests at an isolated PostgreSQL database (the local default is postgres://localhost:5432/nutrition_mcp_test).

The sync journal records explicit MyFitnessPal add authorization as pending only. This slice intentionally makes no real MFP calls and ships no automatic backup scheduler or cloud backup service; backup manifests are a contract for an operator-run backup, not proof that backups ran.

Food-import calls accept at most 50 rows. Each row is limited to 20,000 kcal, 5,000 g for ordinary macros, and 500 g of alcohol; split larger files into chunks while keeping all rows for a calendar date together. The importer is idempotent, but it is not an MFP writer or a cloud backup system.

Self-hosting

This section describes the current local PostgreSQL/Bun runtime. Older Supabase, OAuth, and email/password deployment notes are obsolete and must not be used for this checkout.

1. PostgreSQL and migrations

Create the database named by DATABASE_URL, then apply the migrations in order:

psql "$DATABASE_URL" -v ON_ERROR_STOP=1 -f db/migrations/001_initial_schema.sql
psql "$DATABASE_URL" -v ON_ERROR_STOP=1 -f db/migrations/002_food_tracking.sql

Migration 002_food_tracking.sql is destructive: it deletes the legacy meals rows and drops the legacy meals table before creating the append-only food-tracking schema. Export any data you need before applying it. Migration 002 is safe to rerun after a complete or interrupted run, but it is not a backfill and there is no rollback for the legacy meal reset.

2. Environment variables

Making it yours: The public site includes the maintainer's personal bits — Google Analytics, Patreon/GitHub/contact links, and the nutrition-mcp.com domain. Run bun run depersonalize to strip them all in one pass (analytics + CSP, the Support/Contact sections, social links, and the domain → a your-domain.com placeholder). Use bun run depersonalize --dry to preview without writing. Afterwards, swap in your own public/og.png, favicon.ico, and apple-touch-icon.png, and replace the domain placeholder with your real domain.

Agent-driven meal capture

The complete boundary, lifecycle, provenance, migration, rollback, and retry contract is documented in docs/food-tracking-agent-driven.md.

The append-only meal-event path is also exposed as a transport-neutral, durable capture flow for an agent host. Hermes supplies raw message/evidence/media metadata, clarification answers, prepared drafts, and provider result bundles; this server does not receive Telegram updates, download media, run STT/OCR/vision, or call external MCP servers.

Use start_meal_capture, append_meal_capture_message, answer_meal_capture, and save_meal_capture_draft for restart-safe multi-turn storage. confirm_meal_capture is the explicit authorization gate: only the user's unambiguous add command (including добавь) commits one prepared capture to one meal_event; MyFitnessPal authorization remains a pending journal row, never a claim of successful sync. validate_calculation_bundle accepts and validates Hermes-supplied nutrition-local, own, and myfitnesspal result metadata. Canonical nutrition is recomputed by the existing consensus-10pct-v1 policy; missing, failed, and unavailable values are not treated as zero.

Migration order for a new or test database is 001_initial_schema.sql, 002_food_tracking.sql, then 003_meal_captures.sql.

bun install
cp .env.example .env   # set DATABASE_URL and any local overrides
bun run dev             # starts with hot reload on http://localhost:8080

Run the actual MCP server with bun run start (or bun run src/index.ts). GET /health returns ok; MCP clients must use POST /mcp.

For the full test suite, point integration tests at a disposable database:

DATABASE_URL_TEST=postgres://localhost:5432/nutrition_mcp_test bun test
bun run typecheck
bun run format:check

Connect to Claude.ai

1. Start the server locally with bun run start.

2. Add a custom connector named Nutrition Tracker.

3. Use http://localhost:8080/mcp as the MCP URL.

4. Connect; no sign-in or registration is expected.

API Endpoints

The old OAuth discovery, registration, authorize, approve, and token paths are not part of this runtime.

Deploy

The project includes a Dockerfile for container-based deployment. The container still requires a reachable PostgreSQL DATABASE_URL; it does not provide Supabase or OAuth services.

1. Push your repo to a hosting provider (e.g. DigitalOcean App Platform)

2. Set the runtime environment variables listed above, including DATABASE_URL

3. The app auto-detects the Dockerfile and deploys on port 8080

4. Point your domain to the deployed URL

License

MIT