Connecting an AI assistant

Last updated October 6, 2026

Claude, ChatGPT, Gemini and Grok can each be connected to Lift Day, so that you can tell one what you lifted, or ask it how much cardio you did last week. All four work on a free account. Each signs in to Lift Day and asks you what it may do — there is no key to copy.

You need a Lift Day account first: an athlete joins from their coach's invite link, and a coach signs in and creates a team. Every assistant is given the same address, the Lift Day address:

https://liftday.org/api/mcp

Claude

Claude signs in to Lift Day itself — no key to copy. Add it once at claude.ai in any browser, your phone's included, and it appears in the Claude app afterwards.

Open Claude's connector settings

  1. If you added Lift Day to Claude before, with a key, delete that connector first. Claude won't keep two for the same address.
  2. Settings, then Connectors, then Add custom connector.
  3. Call it Lift Day, paste the Lift Day address, and leave the advanced settings empty.
  4. Add, then Connect. Lift Day opens and asks you to sign in.
  5. Tick what Claude may do, then Allow.

Claude Code on a computer is set up separately. Add it with this, then type /mcp in Claude Code and choose to authenticate:

claude mcp add --transport http liftday https://liftday.org/api/mcp

Tried with claude.ai on 5 October 2026. Claude Code from its documentation — not yet tried.

ChatGPT

ChatGPT connects by signing in. Add Lift Day once in the desktop app, which works on any plan, free included, and it is on chatgpt.com in your browser afterwards too.

  1. Open the ChatGPT desktop app and click Plugins down the left side.
  2. Click Add, then Create MCP App.
  3. Name it Lift Day, paste the Lift Day address as the server URL, and leave Authentication on OAuth.
  4. Tick the box saying you understand, then Create.
  5. Lift Day opens and asks you to sign in. Tick what ChatGPT may do, then Allow.
  6. In a chat, type @ and the name you gave it. The first time it uses each tool, allow it.

Tried with the ChatGPT desktop app on a free account, 5 October 2026, and it then worked on chatgpt.com too. Adding it from the website itself needs a paid plan (Settings, Apps & Connectors, Developer mode).

Gemini

Gemini connects by signing in, from the website only — the phone app picks it up afterwards. Google allows it for personal accounts of people 18 or over in the US, in English, with Keep Activity on.

Open Gemini

  1. Settings, then Personal intelligence, then Connected apps.
  2. Under Custom apps, add one and paste the Lift Day address.
  3. Gemini warns about the risks of connecting a custom app; accept to go on.
  4. Lift Day opens and asks you to sign in. Tick what Gemini may do, then Allow.
  5. If Gemini asks for an OAuth client ID and secret instead, Lift Day turned it away — that is ours to fix, not something to fill in.

The Gemini CLI on a computer signs in too. Add it with this, then run /mcp auth liftday inside it:

gemini mcp add liftday https://liftday.org/api/mcp --transport http

Tried with gemini.google.com on 5 October 2026. The Gemini CLI from its documentation — not yet tried.

Grok

Grok connects by signing in — no key to copy, and no paid plan needed.

Open Grok

  1. Click Plugins at the bottom of the left side.
  2. Click New Connector at the top right, then Custom.
  3. Name it Lift Day, paste the Lift Day address as the Server URL, then Add Connector.
  4. Lift Day opens and asks you to sign in. Tick what Grok may do, then Allow.
  5. In a chat, ask it to check Lift Day — for example, how much cardio you did last week.

Tried with grok.com on a free account, 6 October 2026.

Siri, and anything else

Lift Day lets only Claude, ChatGPT, Gemini and Grok sign in, so that an approval can never be sent anywhere else. Siri, and any other tool that speaks MCP, uses a key instead: sign in to Lift Day, open Settings, then Assistant access, and make one. The steps for the tool you choose — including building a Siri shortcut — appear with the key.

What an assistant may do

Only what you tick when it signs in. The last two are offered to coaches only, and start unticked.

  • Log my lifts. Write sets, reps and weights as me, the way the weight-room kiosk does. Anything written this way is marked as dictated, so you can always tell it apart from what you typed yourself.
  • Read my own training. My sets, cardio, bodyweight and personal bests. Mine only — never anyone else on the team.
  • Read the exercise list. The names of exercises, so it can match what I say to what exists. No training data of any kind.
  • Write the team's programme. Create and edit workout days and the exercises on them. Programmes hold no weights or rep targets, so this cannot prescribe a load to anyone.
  • See what stands out about the team. The findings from the weekly report — who has stopped logging, whose volume has dropped — as conclusions, with athletes identified by a code that means nothing outside this assistant. No names, no email addresses, and no athlete's rows.

There is no permission, for anyone, that reads another person's training — a coach's included. Names and email addresses never leave Lift Day.

Disconnecting

Settings, then Assistant access, lists every assistant you have connected and when each was last used, with a Revoke button that takes effect on its next request. A connection that goes 90 days unused stops working by itself. See also what Lift Day is and the privacy page.