What probably matters to youSection of the release
What
Plugins can start language servers, helper programs that give code intelligence such as go-to-definition. Claude Code already filled in environment variables and plugin options in a server's command, args, env and workspaceFolder. It now does the same inside the nested initializationOptions and settings.
A variable that is not set is left as written and a log line notes it.
A command that ends up empty gets its own error, telling you to set the plugin option or environment variable it refers to.
Why
Plugin authors can pass values such as paths or keys into a language server's options without hard-coding them, and a missing value in the command now produces a clear message.