I have been tweaking the MCP server of FlyFun Weather, and I think it’s starting to be quite useful! The idea is you can have a discussion about your weather briefing, and it’s doing quite well. It get ingested a lot of deterministic/model data and use its own meteorology knowledge. And it has instruction to help advise but not give a “go” or “no go” decision. I am sure people can jail break it and force it to decide, but in normal conversations it should not.
I wonder if that’s will ever become a thing for more people but I personally like ability to dynamically interrogate and discuss a briefing. Example of conversation on this briefing (btw I decided not to do the flight…) https://weather.flyfun.aero/briefing.html?flight=lfmd_perus_domod_lgl_sitet_drake_notgi_evata_egtf-2026-06-21-cdd3
If people try it (with a constructive eye), please let me know feedback where it worked/didn’t work and I’ll tweak.
It works quite well, it’s a nice way to get into the details of the briefing!
I don’t think there’s a way to add to ChatGPT yet, correct?
I am investigating the chatgpt protocol. I will try, I don’t think you can add a custom standard mcp server, so can’t add at the moment
Thanks for this Roznet
Just tried the App for a flight from Husbands Bosworth (nr EGBB) to EHGG/Groningen tomorrow 22nd & very impressed with the detail provided. It’s even better than the good old days when you could call the local Airport Met Man and have a conversation.
Plan to use it for the trip continuing up to Norway – do you want a contribution towards all the tokens it must be burning?
Graham
flying.marmot wrote:
I don’t think there’s a way to add to ChatGPT yet, correct?
Actually, I implemented the openapi (chatgpt MCP equivalent), it works a bit differently in openAI, you have a “Custom GPT” that will know how to talk to FlyFun Weather.
I am a bit new to ChatGPT customization, so here it is, let me know if that works, and be aware, that I gave it the same tools I gave Claude, but I haven’t been talking to it much, so try it and let me know how it behaves, in my few test, I preferred claude response, but maybe need a bit of tweaking.
https://chatgpt.com/g/g-6a3848932b908191b41a58b75404182f-flyfun-weather
GrahamG wrote:
do you want a contribution towards all the tokens it must be burning?
Thanks for the comments on the app. Yes quite a bit of cost, token but also weather data subscriptions…
I have no intention to make it a paid service though, and right now I am happy to sponsor it for while. I actually just added a donation page in the bottom of the help page. I didn’t highlight it yet too much, as it is still a work in progress, but overtime, getting donation will help me make the cost easier to bear and keep the service running.
Hi @roznet, just tried, the ChatGPT integration works great, thanks a lot!
Please have at least a brief look at the charts yourself before deciding if you should take the plane 
The whole game is to constraint the AI to answer right and it can. For your example a simple “think step by step” system prompt works well, see below.
For FlyFun, while I am sure you can try to trick I and trip it, the point here is to build a system prompt that contains a lot of deterministic model derived conclusion and prompt the AI to conclude and analyse following it.
But of course, you should check the deterministic data which is all exposed in the app as well.
