diff --git a/src/code_interpreter/services/custom_tool_executor.py b/src/code_interpreter/services/custom_tool_executor.py
index 4440e74..e1d4084 100644
--- a/src/code_interpreter/services/custom_tool_executor.py
+++ b/src/code_interpreter/services/custom_tool_executor.py
@@ -57,7 +57,8 @@ def parse(self, tool_source_code: str) -> CustomTool:
         Supported types for return value: anything that can be JSON-serialized.
         """
         try:
-            *imports, function_def = ast.parse(textwrap.dedent(tool_source_code)).body
+            tree = ast.parse(textwrap.dedent(tool_source_code))
+            *imports, function_def = tree.body
         except SyntaxError as e:
             raise CustomToolParseError([f"Syntax error: {e.msg} on line {e.lineno}"])
 
@@ -70,6 +71,13 @@ def parse(self, tool_source_code: str) -> CustomTool:
                 ]
             )
 
+        import_aliases = {
+            alias.asname or alias.name
+            for node in imports
+            for alias in node.names
+            if alias.name == "typing"
+        }
+
         errors = [
             x
             for x in (
@@ -104,7 +112,7 @@ def parse(self, tool_source_code: str) -> CustomTool:
             "type": "object",
             "title": function_def.name,
             "properties": {
-                arg.arg: _type_to_json_schema(arg.annotation)
+                arg.arg: _type_to_json_schema(arg.annotation, import_aliases)
                 | (
                     {"description": param_description}
                     if (param_description := param_descriptions.get(arg.arg))
@@ -194,37 +202,52 @@ async def execute(
 
         return json.loads(result.stdout)
 
+def _normalize_type_name(type_node_name: str, aliases: set) -> str:
+    """Normalize type names to their canonical forms."""
+    for alias in aliases:
+        if type_node_name.startswith(f"{alias}."):
+            return type_node_name[len(alias) + 1:].lower()
+
+    return type_node_name
 
-def _type_to_json_schema(type_node: ast.AST) -> dict:
+def _type_to_json_schema(type_node: ast.AST, import_aliases: set) -> dict:
     if isinstance(type_node, ast.Subscript):
-        type_node_name = ast.unparse(type_node.value)
+        type_node_name = _normalize_type_name(ast.unparse(type_node.value), import_aliases)
+
         if type_node_name == "list":
-            return {"type": "array", "items": _type_to_json_schema(type_node.slice)}
+            return {"type": "array", "items": _type_to_json_schema(type_node.slice, import_aliases)}
         elif type_node_name == "dict" and isinstance(type_node.slice, ast.Tuple):
             key_type_node, value_type_node = type_node.slice.elts
-            if ast.unparse(key_type_node) != "str":
-                raise ValueError(f"Unsupported type: {type_node}")
+            key_type_node_name = _normalize_type_name(ast.unparse(key_type_node), import_aliases)
+            if key_type_node_name != "str":
+                raise ValueError(f"Unsupported key type for dict: {ast.unparse(key_type_node)}")
             return {
                 "type": "object",
-                "additionalProperties": _type_to_json_schema(value_type_node),
+                "additionalProperties": _type_to_json_schema(value_type_node, import_aliases),
             }
-        elif type_node_name == "Optional" or type_node_name == "typing.Optional":
-            return {"anyOf": [{"type": "null"}, _type_to_json_schema(type_node.slice)]}
-        elif (
-            type_node_name == "Union" or type_node_name == "typing.Union"
-        ) and isinstance(type_node.slice, ast.Tuple):
-            return {"anyOf": [_type_to_json_schema(el) for el in type_node.slice.elts]}
-        elif (
-            type_node_name == "Tuple" or type_node_name == "typing.Tuple"
-        ) and isinstance(type_node.slice, ast.Tuple):
+        elif type_node_name == "optional":
+            return {"anyOf": [{"type": "null"}, _type_to_json_schema(type_node.slice, import_aliases)]}
+        elif type_node_name == "union" and isinstance(type_node.slice, ast.Tuple):
+            return {"anyOf": [_type_to_json_schema(el, import_aliases) for el in type_node.slice.elts]}
+        elif type_node_name == "tuple" and isinstance(type_node.slice, ast.Tuple):
             return {
                 "type": "array",
                 "minItems": len(type_node.slice.elts),
-                "items": [_type_to_json_schema(el) for el in type_node.slice.elts],
+                "items": [_type_to_json_schema(el, import_aliases) for el in type_node.slice.elts],
                 "additionalItems": False,
             }
-
-    type_node_name = ast.unparse(type_node)
+        elif type_node_name == "literal":
+            if isinstance(type_node.slice, ast.Tuple):
+                return {"enum": [ast.literal_eval(el) for el in type_node.slice.elts]}
+            else:
+                return {"enum": [ast.literal_eval(type_node.slice)]}
+        elif type_node_name == "final":
+            return _type_to_json_schema(type_node.slice, import_aliases)
+        elif type_node_name == "annotated":
+            base_type, *annotations = type_node.slice.elts
+            return _type_to_json_schema(base_type, import_aliases)
+
+    type_node_name = _normalize_type_name(ast.unparse(type_node), import_aliases)
     if type_node_name == "int":
         return {"type": "integer"}
     elif type_node_name == "float":
@@ -233,10 +256,10 @@ def _type_to_json_schema(type_node: ast.AST) -> dict:
         return {"type": "string"}
     elif type_node_name == "bool":
         return {"type": "boolean"}
-    elif type_node_name == "Any" or type_node_name == "typing.Any":
+    elif type_node_name == "any":
         return {"type": "array"}
-    else:
-        raise ValueError(f"Unsupported type: {type_node_name}")
+
+    raise ValueError(f"Unsupported type: {type_node_name}")
 
 
 def _parse_docstring(docstring: str) -> typing.Tuple[str, str, dict[str, str]]: