LanguageServerAPIs The Lanugage Server APIs provides basic facilities for getting or supplying information used by language server implementations.
Completion.getLabelDetail() to get an optional string describing function signatures or type annotations. Completion.getLabelDescription() to get an optional string describing fully qualified names or file path.
CodeActionProvider has been added to allow server provide arbitrary code actions for a given document and range.
CommandProvider has been added to allow server provide arbitrary commands runnable from a client.
LazyCodeAction allows for lazy edit computation.
XXX no answer for arch-usecases
XXX no answer for deploy-dependencies
Read more about the implementation in the answers to architecture questions.