Open Triathlon Coach for ChatGPT
An independent, open-source triathlon coach for ChatGPT that analyses your authorised Intervals.icu activities, wellness, thresholds, and calendar data. Not affiliated with or endorsed by Intervals.icu.
This project is also independent from OpenAI.
Pre-release · Policy baseline 1.0.0 · Reviewed 21 July 2026
What you need
The coach runs inside ChatGPT and connects each athlete to their own Intervals.icu account through OAuth. No software installation, personal API key, athlete ID, or password should be provided in chat.
Its analysis depends heavily on complete data synced from Garmin or another watch or bike computer, Zwift, a smart trainer or power meter, heart-rate sensors, activity files, and wellness sources.
ChatGPT compatibility
Validated: ChatGPT Plus, including OAuth, authenticated reads and a controlled calendar write.
Free test: the GPT opened, but the Intervals.icu custom Action was unavailable, so OAuth could not start. Go has not yet been tested.
Business, Enterprise and Edu workspaces may restrict Action domains. Pro subscribers must use a non-Pro, Action-compatible mode because custom Actions are unavailable in Pro mode.
This is a report of project testing rather than a universal guarantee for every account. Read the compatibility notes.
Reasoning and Action compatibility
Use the highest reasoning level that still keeps the custom Action available. At this policy baseline, OpenAI documents custom Actions as unavailable in Pro mode, so use Extra High when offered with the Action, otherwise High, Medium, or the highest compatible option.
Higher reasoning can reduce some mistakes, but it cannot make AI coaching error-free. Verify thresholds, units, dates, race plans, and account changes.
Privacy summary
The builder has disabled the GPT-level setting labelled “Use conversation data in your GPT to improve our models”. This does not replace each user's OpenAI plan rules or account-level Data Controls.
The project has no separate database, OAuth proxy, or API server. GPT builders cannot view users' individual conversations through the GPT builder. Relevant data may still be processed by OpenAI and Intervals.icu under their own terms and settings.
Status
The Intervals.icu OAuth app is public and the GPT is in public beta through its shared link. End-to-end Action access has been validated on ChatGPT Plus; other plan and workspace combinations remain subject to the compatibility notes.