@markhepburn Thank you for providing the logs, that's very useful and it does seem that yours might be a separate issue.

"languageId":"python-base"

Based on the logs for the open document request, it seems that the server uses python-base as the language ID while ty only recognizes python:

https://github.com/astral-sh/ruff/blob/ee277469d3bddb0d5fd59e308263059561be1e0a/crates/ty_server/src/document/text_document.rs#L39-L46

So, this might be an easy fix.

Originally posted by @dhruvmanila in #2824

But, the spec does recommend to use python: https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#textDocumentItem