[lukax]

It's a bit funny that they use Jedi Language Server for Python as they cannot use Microsoft's own Pylance ("Pylance is licensed for use in Microsoft products and services only, so can only be used on official Microsoft builds of Visual Studio Code and GitHub ...").

They also used Omnisharp Language Server for C# which is deprecated and was replaced with a new extension with custom license terms.

[neonsunset]

There are no special license terms to using Roslyn Language Server, which is what the base C# extension in VSC uses. It is the debugger which is closed-source, and the custom license terms apply mostly to that debugger and to Dev Kit extension which has a subscription. Both are completely optional and there is also an extension fork which uses NetCoreDbg developed by Samsung and licensed under MIT. It is what people usually use when they debug C# in e.g. Neovim.

[craftkiller]

Pyright is billed as a "static type checker" but its a full-blown language server (which pylance is built on). I've used both pylance and pyright and frankly I haven't seen any benefit going up to pylance. Pyright is under the MIT license so it can be used for anything: https://github.com/microsoft/pyright/blob/main/LICENSE.txt

[helsinki]

I use Pyright as my LSP in Neovim and I’m very pleased with it.