FitHarness

Invite only · in trial

A training and nutrition system of record, operated through Claude. You log, plan and change things by talking to Claude; this site is the dashboard for what Claude wrote. Both surfaces do the same things — the web app is not a read-only view.

How it works

The app exposes its whole feature set as an MCP server. Adding it as a connector in Claude gives Claude direct access to your training, nutrition and body data — reading it, writing it, and reasoning over it in the same conversation.

Judgement and arithmetic are split on purpose. Claude decides what a block should look like and how to work around an injury. The app owns the numbers: macro reconciliation, estimated 1RM, progression limits, volume accounting and hard injury constraints are enforced in code, not in prompts. Claude proposes; the app decides what is true and records it.

Everything Claude records shows up here, and every write available through the connector is also available as a form on this site. The web app is the fallback and the visualisation, not a subset.

What it records

Training: Periodized blocks, capped at 12 weeks and chained. Per-lift target weights back-solved from your logged e1RM at the prescribed reps and RPE.
Conditioning: Benchmark WODs, custom metcons, runs and rows, with pace and PR context. Recorded separately from lifting rather than folded into set counts.
Nutrition: Meals by photo or description. Calories are reconciled against the macros behind them, so a stated number that doesn't add up is corrected and flagged.
Body: Weigh-ins with a trailing trend, so a single noisy reading doesn't move anything on its own.
Recovery: Sauna and cold exposure, logged as recovery and never counted as training volume.
Analysis: Working sets per muscle group and movement pattern over any window, push:pull and squat:hinge ratios, and which groups have had nothing.

Example requests

Bench felt heavy — 3×8 at 185, RPE 9. Log it.
I'm travelling. Here's a photo of the hotel gym — rework the next three days around this equipment.
My left elbow has golfer's elbow. Keep training arms but work around it.
I play hockey and the season opens March 1. Build the block backwards from that.
How much hamstring work have I actually done this month?
That took an hour and fifteen. Close the session.

These are requests, not commands — there is no syntax to learn. Anything you would say to a coach is in scope, including arguing with the programming.

Setup

Sign in with Google
The app receives your name and email address. It requests no other scopes — no Gmail, Drive or Calendar access.
Add the connector in Claude, on a computer
Customize → Connectors → Add → Add custom connector, then paste https://fitharness.com/api/mcp and authorize with the same Google account. This step requires the Claude desktop app on a paid plan — the mobile apps cannot add custom connectors. Once added it is saved to your Claude account, so it works from your phone afterwards.
Run the setup interview
Claude asks about your goal, training days, equipment and anything to avoid, then writes your account. This dashboard stays locked until it finishes, and the first training block is generated at the end of it.

Step-by-step with screenshots: connector walkthrough · full docs

Requirements

Invite code: Issued by hand. There is no waitlist and no self-serve signup.
Google account: Used for sign-in only. Name and email address, no other scopes.
Claude: The Claude app on a paid plan, which is what custom connectors require.

Your data

Accounts are isolated. Your connector reaches your own training, nutrition and body data and nothing else. The exercise library is the only shared resource.

Export everything as a single file, or delete the account outright, from Settings. Neither needs a support request. Deletion removes every record the app holds for you; what you have already exported is yours to keep.

Origin

Built at Gadoci Consulting, an AI transformation and services agency, to find out what this generation of models can do when given real write access to a real system rather than a demo. Codes are issued one at a time so the trial stays small enough that someone answers when something breaks. To ask for one, get in touch through the site above.