My only experience is with intellij ides, but this plugin works in both https://www.continue.dev/. We use this internally at my company, and I think it's one of the better open source ones.

At home I use it with open router and ollama/vllm/llama.cpp server

I have been using Cody with VSCodium and it uses Claude by default. I appreciate that it’s not in my face too much, it’s easy to use either the chat interface or in-editor commands/completion. I paid the $15 one month when I was trying it out more heavily and switched back to free for just the occasional chat.

Cline works well for me.