Calorie Cub ›
A calorie tracker MCP server for Claude, ChatGPT and any MCP client
Updated November 6, 2026
TL;DR
Calorie Cub’s MCP server is at https://mcp.caloriecub.com/mcp, and it’s a community connector in Claude’s Connectors Directory. Add it to Claude, ChatGPT, Claude Code, Cursor, Gemini, Grok or any client that supports remote MCP servers, sign in once, and your assistant can search foods, log meals, read your diary and totals, save recipes, and set goals. Reading your diary is free; logging by chat is part of Calorie Cub Pro. This page is the connector’s documentation: every tool, the limits, and what to do when a call fails.
What a nutrition MCP server does
MCP (Model Context Protocol) is the open standard assistants use to call tools in other apps. A nutrition MCP server gives your assistant a small set of tools: look up a food, write an entry to your diary, read today’s totals. You keep talking to the assistant; the server keeps the record.
Calorie Cub exposes 20 tools: search_foods, get_food, log_meal, update_meal, delete_meal, copy_meals, get_diary, get_summary, get_recent_foods, get_favorites, set_favorite, save_food, suggest_food_correction, save_recipe, get_recipe, get_goals, set_goals, log_weight, get_weights and send_feedback. Each one does one thing, so an assistant can chain them: search for “oatmeal”, pick the plain cooked serving, log it to breakfast, then read back what’s left for the day.
The server, in one block
URL: https://mcp.caloriecub.com/mcp
Transport: Streamable HTTP, stateless
Auth: OAuth 2.1 with PKCE and dynamic client registration (or a personal API key)
Scopes: diary:read, diary:write, library:write, goals:write
Clients that read a config file want this:
{
"mcpServers": {
"calorie-cub": { "url": "https://mcp.caloriecub.com/mcp" }
}
}
In Claude Code, one command adds it and /mcp signs you in:
claude mcp add --transport http calorie-cub https://mcp.caloriecub.com/mcp
Which clients connect
In Claude, Calorie Cub is a community connector in the Connectors Directory. Other clients add it by address:
Add Calorie Cub from Claude’s Connectors Directory ›Claude (web, desktop, mobile)
How to add it: Connectors Directory › Calorie Cub › Add
Notes: Or Customize › Connectors › Add custom connector with the URL
Claude Code
How to add it: claude mcp add --transport http calorie-cub …
Notes: Then /mcp to sign in
ChatGPT (web)
How to add it: Plugins › + › Add custom MCP server, choose OAuth
Notes: Install it from your personal plugins; @Calorie Cub in a chat
Gemini
How to add it: Settings › Connected Apps › Custom apps
Notes: Adults in the US on personal accounts; connect on the web
Grok
How to add it: grok.com/connectors › New Connector › Custom
Notes: Grok Bot: ask your Bot to add a custom MCP server
Cursor, VS Code, other clients
How to add it: Add a remote MCP server with the URL
Notes: OAuth if the client supports it, otherwise a personal API key
Tools, and the permission each one needs
Each tool needs one scope, which you approve when you connect. Read tools are marked read-only; update_meal, delete_meal, set_goals and log_weight are marked destructive, so your client can ask you before it runs them. Dates are your local dates (YYYY-MM-DD).
search_foods
What it does: Searches the catalog and your private foods, and returns serving ids to log with
Scope: diary:read
Plan: Free
get_food
What it does: One food with its servings and nutrition
Scope: diary:read
Plan: Free
get_recent_foods
What it does: Foods you logged most recently
Scope: diary:read
Plan: Free
get_favorites
What it does: Foods and recipes you starred
Scope: diary:read
Plan: Free
get_recipe
What it does: A recipe with its ingredients, per-serving nutrition and totals
Scope: diary:read
Plan: Free
get_diary
What it does: Entries and totals for one date
Scope: diary:read
Plan: Free
get_summary
What it does: Daily totals for a date range of up to 31 days
Scope: diary:read
Plan: Free
get_goals
What it does: Your timezone, units and daily goals
Scope: diary:read
Plan: Free
get_weights
What it does: Recent weight entries, newest first
Scope: diary:read
Plan: Free
log_meal
What it does: Logs a food serving to a meal on a date; the server computes the nutrition
Scope: diary:write
Plan: Pro
update_meal
What it does: Changes an entry’s quantity, meal or date (needs the entry’s current version)
Scope: diary:write
Plan: Pro
delete_meal
What it does: Deletes one diary entry
Scope: diary:write
Plan: Pro
copy_meals
What it does: Copies entries from one date, or one meal, to another date
Scope: diary:write
Plan: Pro
log_weight
What it does: Records body weight in kg for a date, replacing that date’s value
Scope: diary:write
Plan: Pro
save_food
What it does: Creates a private custom food; nutrition you estimate is labeled estimated
Scope: library:write
Plan: Pro
save_recipe
What it does: Creates a private recipe from foods, with nutrition per serving of the yield
Scope: library:write
Plan: Pro
set_favorite
What it does: Stars or unstars a food or recipe
Scope: library:write
Plan: Pro
suggest_food_correction
What it does: Sends a correction for review; official records are never edited directly
Scope: library:write
Plan: Pro
set_goals
What it does: Updates calorie and macro goals, units or timezone
Scope: goals:write
Plan: Pro
send_feedback
What it does: Sends the Calorie Cub team your feedback when you’re stuck, only after you say yes; 3 a day
Scope: diary:read
Plan: Free
Free and Pro limits
Tools
Free: The 9 read tools and send_feedback (diary:read)
Pro: All 20 tools
Connected apps
Free: 1
Pro: Unlimited
Tool calls per day
Free: 200
Pro: 2,000
Personal API keys
Free: 1
Pro: 5
Price
Free: Free, no time limit
Pro: $6.99 a month, or $39.99 a year with a 3-day free trial
Daily calls reset at 00:00 UTC. Only tool calls count; connecting and listing tools don’t. Each account also has a short burst limit, so an agent that loops can’t lock you out of your own app.
Connect and disconnect
- •Claude: open Calorie Cub in the Connectors Directory, select Add, sign in to Calorie Cub and approve access. Then turn it on for a chat from + › Connectors.
- •Any other client: add https://mcp.caloriecub.com/mcp as a remote MCP server. The client opens a Calorie Cub sign-in page; sign in and approve the access it asks for.
- •Clients without OAuth: create a personal API key in Settings › API keys and send it as Authorization: Bearer cc_…. A read key can only read.
- •Disconnect: in Calorie Cub, open Settings › Connected apps and select Revoke. The app loses access on its very next call. Revoke an API key the same way under API keys. Removing the connector in your client stops it from calling, too.
Errors and troubleshooting
A failed tool call returns one of these messages, so the assistant can tell you what happened:
insufficient_scope: <scope>
What it means: The app wasn’t granted the permission this tool needs
What to do: Disconnect the app, connect again and approve that permission
plan_limit: <scope> needs Calorie Cub Pro
What it means: A write tool was called on the Free plan
What to do: Start the 3-day free trial at caloriecub.com/pro; writes work on the same connection right away, with no reconnect
daily_limit_reached
What it means: Your plan’s tool calls for today are used up
What to do: Wait for the reset at 00:00 UTC, or upgrade to Pro
rate_limited (HTTP 429)
What it means: Too many calls in a short burst
What to do: Wait about 10 seconds, then retry
app_limit_reached
What it means: The Free plan allows one connected app and another is connected
What to do: Revoke the other app in Settings › Connected apps, then connect again
invalid_token or grant revoked (HTTP 401)
What it means: The app was disconnected or its sign-in expired
What to do: Reconnect it in your client and sign in again
invalid_api_key (HTTP 401)
What it means: The API key is wrong or was revoked
What to do: Create a new key in Settings › API keys
Input validation error
What it means: An argument doesn’t match the tool’s schema, such as a date that isn’t YYYY-MM-DD
What to do: Fix the argument the message names, then retry
serving_not_found
What it means: The serving_id doesn’t belong to that food
What to do: Call search_foods or get_food again and use one of its serving ids
food_not_found, entry_not_found
What it means: The id doesn’t exist or belongs to someone else
What to do: Search again, or read the diary again for current ids
version_conflict
What it means: The entry changed after it was read
What to do: Read it again with get_diary and retry with the current version
idempotency_conflict
What it means: An idempotency_key was reused for a different request
What to do: Use a fresh key for each new entry; reuse one only to retry the same request
internal_error
What it means: Something failed on our side
What to do: Retry once; if it keeps happening, contact support
- •Claude doesn’t use Calorie Cub: turn it on for that chat from + › Connectors, or mention Calorie Cub in your message.
- •The tools don’t show up after you connect: remove the connector and add it again. Most clients load the tool list only when they connect.
- •A logged meal looks wrong: open it in the app to see which food and serving the assistant picked, then edit it there or ask the assistant to fix it.
- •Still stuck: email support with the tool name, the time and the error message. Never send passwords, API keys or tokens.
Why it looks foods up instead of guessing
A language model is good at understanding “a grande iced latte with oat milk” and bad at remembering how many calories that is. Calorie Cub keeps those jobs apart. The assistant works out what you meant and calls search_foods; the numbers come from a catalog built on USDA data and restaurants’ own published nutrition guides, including the menus of more than 70 US chains, item by item and size by size. Every food is labeled official, reviewed, or estimated, so you can see how far to trust it.
Every write carries a one-time key, so a retried request can’t log a meal twice. If a food isn’t in the catalog, the assistant can save it as your own custom food, labeled estimated, and you can correct it later.
What studies found about AI calorie estimates ›Browse the restaurant menus ›Do MyFitnessPal, Cronometer, Lose It! or MacroFactor have MCP servers?
Not official ones, as of November 2026. What exists:
- •MyFitnessPal: no MCP server, Claude connector, or public API. Its ChatGPT app answers questions without logging. Community servers sign in with your password and broke when the site moved behind bot protection.
- •Cronometer: no official server. Community projects use a reverse-engineered API or your password; one needs a Gold account.
- •Lose It!: no official server. A community server was reverse-engineered from the web app’s traffic and needs your login.
- •MacroFactor: no official server yet. Its 2026 annual report says it’s building App Intents on iOS and AppFunctions on Android as an MCP-style bridge for AI agents. A community server reads the app’s data export instead.
Other nutrition MCP servers, and where Calorie Cub differs
There are good open-source options. Nutrition MCP is a free remote server backed by USDA and Open Food Facts data. Calories Club is an app with a remote server and a ChatGPT listing. Local servers such as daily-calorie-tracker keep a SQLite file on your own machine. What’s different here:
- •OAuth with scopes: your assistant never sees a password, and you choose read-only or write access per app, revocable in Settings.
- •A diary you can open: the same entries appear in the Calorie Cub app on the web and iPhone, with photo, voice, barcode, and search logging for when a sentence is slower.
- •Provenance on every food: official, reviewed, or estimated, including restaurant menus from the chains’ own nutrition guides.
- •Writes that can’t double up, a daily quota that protects your account, and export or deletion of everything from Settings.
Security and privacy
Sign-in is OAuth 2.1 with PKCE and dynamic client registration, so any client can register itself and no shared secret is involved. You approve scopes once, and each connected app shows in Settings, where disconnecting it takes effect immediately. Tool calls count against a daily quota that resets at midnight UTC.
Calorie Cub doesn’t sell data or show ads. What you say to an assistant, including diary data it reads, also goes to that assistant’s company under its own privacy policy.
Read the privacy policy ›For developers
The auth flow, scopes, personal API keys, and quotas are documented at caloriecub.com/auth.md. An agent skill file that teaches an assistant how to use the tools is at caloriecub.com/agent-skills/calorie-cub/SKILL.md, and caloriecub.com/llms.txt lists every public page. REST lives under /api with the same session.
auth.md: OAuth, API keys and limits ›SKILL.md: how an agent should use Calorie Cub ›What Calorie Cub costs
Tracking in the Calorie Cub app is free with no time limit, and the free plan lets one assistant read your diary. Logging, editing, and setting goals by chat is part of Pro: $6.99 a month, or $39.99 a year with a 3-day free trial. Your assistant’s own subscription is separate.
Questions people ask
Is the Calorie Cub MCP server free?
Connecting and reading your diary is free: one assistant can read on the free plan. Logging, editing, and setting goals by chat is part of Pro, $6.99 a month or $39.99 a year with a 3-day trial.
Do I need an API key?
No. Clients that support OAuth sign in through your browser. Personal API keys exist for scripts and clients without OAuth; create one in Settings.
Does it work with Cursor or VS Code?
Yes. Any client that can add a remote MCP server by URL can use it, with OAuth where supported or a personal API key otherwise.
Does it read Apple Health or my workouts?
No. Calorie Cub tracks food, weight, and goals. It doesn’t read Apple Health or exercise data.
Is Calorie Cub in the ChatGPT or Claude directories?
Claude: yes. Calorie Cub is a community connector in Claude’s Connectors Directory, approved in November 2026. ChatGPT: submitted and in review, so add it there by address using the steps above.
What’s the difference between MCP and an API?
An API is for programs you write. MCP is for assistants: it describes tools in a way a model can read and call on its own, with sign-in handled by the client. Calorie Cub offers both.
Other guides
Use ChatGPT to help you diet ›ChatGPT diet plan and meal plan prompts ›Is ChatGPT accurate for calories? ›Use Claude to help you diet ›Use Gemini to help you diet ›Use Grok and Grok Bot to help you diet ›AI calorie counter: photo, voice, or chat ›How logging meals by chat works ›Is there a MyFitnessPal MCP server? ›Is there a MyFitnessPal API? ›MyFitnessPal alternatives compared ›Cal AI alternatives ›Try Calorie Cub free
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How Calorie Cub works