TL;DR
Claude can connect to a real food diary on every plan, including Free. Add https://mcp.caloriecub.com/mcp as a custom connector, and Claude can read your diary and goals before it suggests anything. With Calorie Cub Pro, it can log meals for you too. Pair it with a Project that holds your goals, and you won’t have to explain yourself each time.
What changes when Claude can see your diary
Without a connection, Claude only knows what you tell it in that chat. Ask what to have for dinner and you’ll get a generic answer.
With Calorie Cub connected, Claude can check what you’ve eaten today and how much of your goal is left, then answer with that in mind. The numbers come from the Calorie Cub catalog, and what it logs lands in the same diary you see in the app on the web and iPhone.
How to connect Claude to Calorie Cub
Calorie Cub isn’t in Claude’s connector directory yet. We’ve submitted it, but it isn’t live, so add it by address:
- 1.On claude.ai or in Claude Desktop, go to Customize, then Connectors.
- 2.Select + Add, then Add custom connector.
- 3.Name it Calorie Cub, enter https://mcp.caloriecub.com/mcp, and select Continue.
- 4.Keep the sign-in settings Claude detects, continue, then select Add.
- 5.Sign in to Calorie Cub and approve what Claude may do.
- 6.In a new chat, select + in the lower left, open Connectors, and turn on Calorie Cub.
On Claude’s Free plan you get one custom connector, so this would be it. Team and Enterprise members need an admin to add the connector first. Anthropic also moves these menus now and then; if a label doesn’t match, look for the option to add a custom connector by URL.
Set up a Project for your diet
A Claude Project keeps instructions in one place for every chat inside it. Create one called “Food diary” and paste something like this into its instructions:
I keep my food diary in Calorie Cub. Before suggesting a meal, check today's diary and my goals. Look foods up in Calorie Cub before logging them, and ask about the portion if I didn't give one. Tell me which serving you picked. I don't eat fish. Don't suggest skipping meals, and tell me to ask a clinician about medical questions.
Change the details to suit you. Remember to turn the connector on in chats where you want it.
Prompts to try
- •“What’s left in my goals today? Suggest two dinners that fit, using what I usually eat.”
- •“Pull my last 14 days and make a chart of calories against my goal.”
- •“Look at my diary for the past week. Where does most of my sugar seem to come from, and which foods would be easiest to swap?” (Ask it to name the entries, so you can check.)
- •“I’m going to Olive Garden tonight. Find options that fit what I have left.”
With Calorie Cub Pro, you can also change the diary:
- •“Log a Chick-fil-A Spicy Chicken Sandwich for lunch.”
- •“Here’s a recipe I’m making tonight. Save it to Calorie Cub as six servings, and tell me which ingredients you’re unsure about.”
- •“Copy yesterday’s breakfast to today.”
- •“Make that lunch half a serving.”
- •“I weighed 172 pounds this morning.”
Using Claude Code
If you already spend your day in a terminal, you can log from there too. One command adds the connection. Then run /mcp inside Claude Code to sign in:
claude mcp add --transport http calorie-cub https://mcp.caloriecub.com/mcp
After that, “log a turkey sandwich for lunch” works between other tasks.
Where Claude still needs you
Portions are the weak spot. “A bowl of pasta” could be 300 calories or 900, so give a size or a weight when it matters, and check the serving Claude picked.
Insights are only as good as your diary. A week with missing meals will produce confident conclusions from incomplete data, so tell Claude when you skipped logging.
Claude may ask for your permission before it uses a tool. You control that, along with what Calorie Cub lets it do. Disconnect it in Calorie Cub’s Settings and it loses access immediately.
What you ask Claude, including diary data it reads, is also sent to Anthropic under its privacy policy.
Food diary, not medical advice
Claude and Calorie Cub can help you keep track and think through options, but neither is a doctor or dietitian, and an assistant can be wrong with total confidence. If you’re pregnant, have diabetes or another condition, take weight-loss medication, or have a history of disordered eating, talk to a clinician before changing how you eat.
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
Can Claude track calories on the free plan?
Claude’s Free plan allows one custom connector, so you can connect Calorie Cub. On Calorie Cub’s free plan Claude can read your diary; logging by chat needs Calorie Cub Pro.
Can Claude make me a meal plan?
Yes, and with your diary connected it can plan around your goals and the foods you actually log. Treat it as a draft you can adjust. Calorie Cub stores your diary, not the plan itself.
Does it work in the Claude mobile app?
Connectors added to your Claude account are available in the mobile apps. Set it up on the web or in Claude Desktop first.
Is there a calorie tracker skill for Claude?
We publish a skill file at caloriecub.com/agent-skills/calorie-cub/SKILL.md that teaches an agent how to use Calorie Cub. It’s instructions only, so Claude still needs the connector above to reach your diary.
Is Calorie Cub in Claude’s connector directory?
Not yet. It’s been submitted but isn’t live, so use the custom connector steps above.
Other guides
Use ChatGPT to help you diet ›ChatGPT diet plan and meal plan prompts ›Is ChatGPT accurate for calories? ›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 ›Try Calorie Cub free
Sign in with Google, then log from the app or connect your assistant. No card needed.
How Calorie Cub works