Sounds like MoE but more pluggable. Not sure if anyone is researching something like this. I still think your swift or GIS model will need basic reasoning and coding to work, so it's more like multiple smaller models which you can load as needed, e.g. sub-agents for GIS needs the GIS model.
Another approach would be to have basic coding and reasoning model and then load specification for language and libraries into context, it could work for self-hosted models, but I don't want whole specification of the language to be send to API and waste tokens on that.
My motivation is somehow the model should be able to work without hitting an external resource every single time and somehow have all the knowledge necessary locally so we don't get rate limited but how can you stay up to date with the latest information while still remaining a good boy scout by not reaching out to tool use and scraping every single GitHub repo and issue every single time?