diff --git a/examples/example.il b/examples/example.il
index 6fb57eb..c76df28 100644
--- a/examples/example.il
+++ b/examples/example.il
@@ -5,11 +5,11 @@ example2 = example
 (
   (let (some vars (default 0))
     ; ... some wall of text
-    "))"
-
+    "))\""
     wqdqwf = '(doqwf) 
     var = 1.3
     var = 231
     qqvwv
+    cfunc()
   )
 )
diff --git a/skillls/main.py b/skillls/main.py
index c98c77e..d7cc287 100644
--- a/skillls/main.py
+++ b/skillls/main.py
@@ -1,17 +1,34 @@
+from collections.abc import Generator
 from logging import INFO, basicConfig, getLogger
+from re import fullmatch
+import re
 from time import time
 from lsprotocol.types import (
+    TEXT_DOCUMENT_DID_CHANGE,
     TEXT_DOCUMENT_DID_OPEN,
     TEXT_DOCUMENT_DID_SAVE,
     TEXT_DOCUMENT_DOCUMENT_SYMBOL,
+    TEXT_DOCUMENT_HOVER,
+    TEXT_DOCUMENT_INLAY_HINT,
     CompletionItem,
+    Diagnostic,
+    DiagnosticSeverity,
+    DidChangeTextDocumentParams,
     DidOpenTextDocumentParams,
     DidSaveTextDocumentParams,
     DocumentSymbol,
     DocumentSymbolParams,
+    Hover,
+    HoverParams,
+    InlayHint,
+    InlayHintParams,
+    MessageType,
+    Position,
+    Range,
 )
 
 from pygls.server import LanguageServer
+from pygls.workspace import TextDocument
 
 from skillls.parsing.iterative import IterativeParser, TokenParser
 
@@ -24,35 +41,97 @@ basicConfig(filename="skillls.log", level=INFO)
 cache: Cache[str, CompletionItem] = Cache()
 
 logger = getLogger(__name__)
-server = LanguageServer("skillls", "v0.1")
 
 
-@server.feature(TEXT_DOCUMENT_DOCUMENT_SYMBOL)
-def on_hover(params: DocumentSymbolParams) -> list[DocumentSymbol]:
-    server.workspace.remove_text_document(params.text_document.uri)
-    doc = server.workspace.get_text_document(params.text_document.uri)
-    t = TokenParser()
-    t.prepare_content(doc.source)
+class SkillLanguageServer(LanguageServer):
+    def _diagnose_parens(self, doc: TextDocument) -> Generator[Diagnostic, None, None]:
+        open: list[tuple[int, int]] = []
+        in_str: bool = False
+        last = ""
+        for row, line in enumerate(doc.lines):
+            for col, char in enumerate(line):
+                match char:
+                    case "(":
+                        if not in_str:
+                            open.append((row, col))
+                    case ")":
+                        if not in_str:
+                            if len(open) > 0:
+                                open.pop()
+                            else:
+                                yield (
+                                    Diagnostic(
+                                        Range(
+                                            Position(row, col),
+                                            Position(row, col),
+                                        ),
+                                        "unopened ) encountered",
+                                    )
+                                )
+                    case '"':
+                        if not (in_str and last == "\\"):
+                            in_str = not in_str
+                    case _:
+                        last = char
 
-    return t._token_tree
+                last = char
+
+        if len(open) > 0:
+            for row, col in open:
+                yield (
+                    Diagnostic(
+                        Range(Position(row, col), Position(row, col)),
+                        "unclosed ) encountered",
+                    )
+                )
+
+    def _diagnose_cisms(self, doc: TextDocument) -> Generator[Diagnostic, None, None]:
+        for row, line in enumerate(doc.lines):
+            for col, char in enumerate(line):
+                if col > 0:
+                    if fullmatch("\\w", line[col - 1]) and char == "(":
+                        if m := re.match(r"\W+(\w+)$", line[:col]):
+                            tok = m.group(1)
+                        else:
+                            tok = line[col - 1]
+                        yield Diagnostic(
+                            Range(
+                                Position(row, col - len(tok)),
+                                Position(row, col + 1),
+                            ),
+                            f"c-ism detected: change to `( {tok}`",
+                            DiagnosticSeverity.Warning,
+                        )
+
+    def diagnose(self, doc: TextDocument) -> None:
+        diags: list[Diagnostic] = []
+
+        diags.extend(self._diagnose_parens(doc))
+        diags.extend(self._diagnose_cisms(doc))
+
+        self.publish_diagnostics(doc.uri, diags)
+
+
+server = SkillLanguageServer("skillls", "v0.2")
 
 
 @server.feature(TEXT_DOCUMENT_DID_OPEN)
-def on_open(params: DidOpenTextDocumentParams) -> None:
+def on_open(ls: SkillLanguageServer, params: DidOpenTextDocumentParams) -> None:
     doc = server.workspace.get_text_document(params.text_document.uri)
-    p = IterativeParser()
-    diags = p(doc.lines)
-    server.publish_diagnostics(params.text_document.uri, diags, version=int(time()))
+    ls.diagnose(doc)
 
 
-@server.feature(TEXT_DOCUMENT_DID_SAVE)
-def on_save(params: DidSaveTextDocumentParams) -> None:
-    server.workspace.remove_text_document(params.text_document.uri)
+@server.feature(TEXT_DOCUMENT_DID_CHANGE)
+def on_save(ls: SkillLanguageServer, params: DidChangeTextDocumentParams) -> None:
     doc = server.workspace.get_text_document(params.text_document.uri)
-    p = IterativeParser()
-    diags = p(doc.lines)
-    logger.warning(doc.source)
-    server.publish_diagnostics(params.text_document.uri, diags, version=int(time()))
+    ls.diagnose(doc)
+
+
+@server.feature(TEXT_DOCUMENT_INLAY_HINT)
+def inlay_hints(ls: SkillLanguageServer, params: InlayHintParams) -> list[InlayHint]:
+    hints: list[InlayHint] = []
+
+    return hints
 
 
 def main():