Cool! 
Edit: Please see https://forum.intervals.icu/t/the-ai-coach-we-self-coached-athletes-want for some more ideas.
Honestly, I was wondering for a few weeks already – using atheltica.ai and looking at similar AI-based coaching platforms – that we should really pick the old Un*x approach and build tools that are great for one purpose. We have intervals.icu for collecting, visualizing, and analyzing our data, incl. planned events (races, holidays, etc.) and our notes on wellness and workouts.
We need an AI coach that “simply” takes this info and creates and updates our plan regularly.
I came to the forum to write about this and see you are already going along that way!
I chatted with your bot and created a plan draft for the next months – aiming at a race in March.
Currently I am at ~50 % budget and it is “thinking” about the plan for a while (since 79 % or so); my last input was “Please create the plan and sync to intervals.icu”.
Would I be happy to pay for it. Sure, I do pay for athetlica.ai and have paid for other platforms before. I would suggest a free trial plus a monthly subscription fee maxing out at ~20 €.
It would be great if it could use my existing chatgpt, or similar, subscription to get better performance and/or lower price.
Features I would like:
- check in with intervals.icu after every finished workout
- actually use the i.icu activity chat to interact with the AI coach – as I would do with a human coach, too. More extensive discussions could still go through the extra interface, but the routine “workout was fine” or “too hard/easy, please adjust” as well as “felt sick, need to reduce the next days” could/should be possible through the i.icu chat😉
- adjust plan dynamically, e.g., once a day (night)
- pick up new races/events and notes (sick, holiday, etc.) from i.icu automatically and adjust plan accordingly. That’s one shortcoming other AI coaches have: they often do not act on no-training days beforehand but only adjust the workouts after. They should be seen as potential recovery days allowing for hard days just before… (I often do adjust this manually…)
Surely I had many more ideas in mind, will add.
How much data on endurance training, success, etc. is there available in these general AI models? For instance, the strength of TrainerRoad, Xert, whatever is there (sometimes) huge amount of data from many atheletes between which they can compare and cross-correlate performance and prescription/mocdeling of plans?
This is a great effort and I hope you can really make it work!
One thing I was wondering if intervals.pro, with such a close doubling, is a good name. First, did you ask @david if he is happy with it? Second, is it really what you want? You do not want to do the job of intervals, you want to be that other tool, with a really different purpose, and not be confused with intervals.icu – you might use the benefit from the association to wonderful interval.icu in the startup, but not in the long run. Why not call it AI-coach.icu? 
PS: It seems to be stuck at 49 % and “thinking” is not blinking anymore… I’ll send you the last “reasoning” as PM.