The 0xCal connector lets ChatGPT, Claude, Grok Bot or any assistant that supports MCP work with your real food log: review a day or a week, tell you how many calories and how much protein you have left, rate your day, plan tomorrow, log a meal from a description and set the daily goals you agreed on.
What you need
- An iPhone with 0xCal and an active subscription
- An assistant that supports MCP connectors (ChatGPT, Claude, Grok Bot and others)
Connect
- In 0xCal, open Profile → AI assistants and choose Ask every time or Automatic. Allow notifications: requests reach your phone as notifications.
- In your assistant, add 0xCal from its connector directory, or add a custom connector with the address
https://0xcal.app/mcp. - Press Connect. A 0xCal page opens with a code. On your iPhone, open the link or enter the code in Profile → AI assistants, pick what the assistant may do, and approve.
What the assistant can do
| Tool | What it does | Permission |
|---|---|---|
get_meals | Meals for a day or a range of up to 31 days: time, description, calories, protein, carbs, fat, and daily totals | Meals |
get_daily_summary | A day's calorie budget: goal, eaten, burned in workouts, remaining, and macros against your targets | Calorie balance |
log_meal | Adds a meal from a description; 0xCal estimates calories and macros on your phone | Logging meals |
set_goals | Sets your daily calorie goal and/or protein, carbs and fat targets, as in Program | Daily goals |
Try: “What did I eat yesterday?”, “How many calories do I have left today?”, “Log two scrambled eggs and a slice of rye bread”, “Set my goal to 1,800 kcal with 150 g protein”.
Your meals stay on your iPhone
0xCal keeps no copy of your meals on its server. When the assistant asks, the server sends a notification to your iPhone, the app answers with only what was asked for, and the server passes the answer on and deletes it. You choose how the app answers:
- Off: no assistant gets anything.
- Ask every time: each request shows what would leave your phone, with Allow and Decline.
- Automatic: you pick which actions run on their own; changing your goals asks first unless you turn it on.
Every request is listed in the app's history. What the assistant receives is handled under its provider's privacy policy. Details: Privacy Policy.
Disconnect
In Profile → AI assistants, remove the assistant from the connected list, or choose Off to stop all of them at once. You can also remove the connector in the assistant's settings.
Troubleshooting
- “Could not reach the user's iPhone”: open 0xCal once and make sure notifications are allowed.
- “The user did not approve the request”: at Ask every time, answer the notification or the card above Today within about a minute.
- Older days missing at Automatic: the app answers on its own for the last 92 days; for older days choose Ask every time.
Help
Write to support@0xcal.app.