I wonder, is the problem here that LSP is updating too slow all the time? Or just that there’s a chance it will update very slow, and you never really know if you’ll hit that chance, so your model always has to do the “long time wait” just in case? It seems like it ought to be possible for LSP to report that it is still processing, in the latter case, somehow…

I'm not an expert, but my reading of the spec is that LSP can handle generic $notifications, but there isn't a specific standard for readiness reporting beyond "Initialize / Initialized", which isn't suitable for monitoring on-going staleness or readiness post-file-detected change, the spec has that as a single first-time initialization.

There are notifications (i.e. `textDocument/didChange` ) that you can send to the LSP to help it along, but again you might end up racing the notification from the client making the change and any file-watchers you might have running.

I suspect the answer will come in the form of some kind of more powerful LSP implementations with generous memory caches so that disk changes are just another buffered input that can be disregarded if already stale, no longer seen as the source of truth, and the LSP becomes the real source of truth, so everything can coordinate through it, operating mostly out of memory.

Another avenue for better success will be more research into faster compilation and better incremental compilation for languages with slower compilation.

Maybe one day we'll even get AI agents directly manipulating syntax trees, and the code to get there being written back as merely a side-effect, but that seems like sci-fi compared to the current state of play. LSP is still very document based, and of course LLMs are also trained on oodles of source.