diff --git a/tests/fuzz.py b/tests/fuzz.py
index 81a9058..6f1fb06 100644
--- a/tests/fuzz.py
+++ b/tests/fuzz.py
@@ -7,25 +7,28 @@ from blueprintcompiler.outputs.xml import XmlOutput
 
 sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
 
-from blueprintcompiler import decompiler, gir, parser, tokenizer, utils
+from blueprintcompiler import gir, parser, tokenizer
 from blueprintcompiler.completions import complete
 from blueprintcompiler.errors import (
-    CompileError,
     CompilerBugError,
-    MultipleErrors,
     PrintableError,
 )
-from blueprintcompiler.tokenizer import Token, TokenType, tokenize
+from blueprintcompiler.lsp import LanguageServer
+
+fuzz_level = int(os.getenv("FUZZ_LEVEL") or "0")
 
 
 @PythonFuzz
-def fuzz(buf):
+def fuzz(buf: bytes):
     try:
         blueprint = buf.decode("ascii")
 
         tokens = tokenizer.tokenize(blueprint)
         ast, errors, warnings = parser.parse(tokens)
 
+        if fuzz_level >= 1:
+            assert_ast_doesnt_crash(blueprint, tokens, ast)
+
         xml = XmlOutput()
         if errors is None and ast is not None:
             xml.emit(ast)
@@ -37,6 +40,17 @@ def fuzz(buf):
         pass
 
 
+def assert_ast_doesnt_crash(text, tokens, ast):
+    lsp = LanguageServer()
+    for i in range(len(text) + 1):
+        ast.get_docs(i)
+    for i in range(len(text) + 1):
+        list(complete(lsp, ast, tokens, i))
+    for i in range(len(text) + 1):
+        ast.get_reference(i)
+    ast.get_document_symbols()
+
+
 if __name__ == "__main__":
     # Make sure Gtk 4.0 is accessible, otherwise every test will fail on that
     # and nothing interesting will be tested