[Jcampuzano2]

To be fair in every harness I've ever used that has LSP support, they never actually utilize the LSP for more deterministic refactoring tools. And even then when I do enable the LSP in many harnesses oftentimes it doesn't even use it at all.

Maybe they haven't been taught to do so or it's not integrated into the system prompt or the tools but all of them only ever use the LSP to read files/symbols.

Every harness I've used will happily just call the edit tool over and over or do a find and replace via sed or programatically call a python/perl script rather than rename a symbol via other means.

[caspar]

This is partially a "how much does the model follow instructions" thing. I use Pi with a vibed LSP extension and Claude (4.6 or thereabouts) almost never followed instructions to use LSP renaming tools - despite it being strongly emphasized in system prompt and agents.md. However I found Codex 5.3 would use them sometimes, and GPT 5.4/5.5 would prefer them.