Agent Framework + middleware + source generation is the way to go.

Agent Framework made middleware much easier to work with.

Source generation makes it possible to build "strongly typed prompts"[0]

Middleware makes it possible to substitute those at runtime if necessary.

[0] https://github.com/CharlieDigital/SKPromptGenerator/tree/mai...

we have been using Agent Framework. I also have been eyeing LlmTornado. Personally, I find dotnet as a whole hard to implement the kind of abstractions I want to have to make it ergonomic to implement AI stuff.

I've been fiddling around with many prototypes to try to figure out the right way to do this, but it feels challenging; I'm not yet familiar enough with how to do this ergonomically and idiomatically in dotnet haha