diff --git a/logfire-api/logfire_api/__init__.py b/logfire-api/logfire_api/__init__.py
index b7b8fc728..cf24f1bd8 100644
--- a/logfire-api/logfire_api/__init__.py
+++ b/logfire-api/logfire_api/__init__.py
@@ -193,6 +193,8 @@ def loguru_handler() -> dict[str, Any]: ...
         def no_auto_trace(x):
             return x
 
+        def add_non_user_code_prefix(*args, **kwargs) -> None: ...
+
         @contextmanager
         def suppress_instrumentation():
             yield
diff --git a/tests/test_logfire_api.py b/tests/test_logfire_api.py
index 2f6306661..9d7b18132 100644
--- a/tests/test_logfire_api.py
+++ b/tests/test_logfire_api.py
@@ -94,6 +94,10 @@ def test_runtime(logfire_api_factory: Callable[[], ModuleType], module_name: str
     logfire_api.no_auto_trace(lambda: None)  # pragma: no branch
     logfire__all__.remove('no_auto_trace')
 
+    assert hasattr(logfire_api, 'add_non_user_code_prefix')
+    logfire_api.add_non_user_code_prefix('.')
+    logfire__all__.remove('add_non_user_code_prefix')
+
     assert hasattr(logfire_api, 'suppress_instrumentation')
     with logfire_api.suppress_instrumentation():
         ...