improve docs again

docs/source/plugin-api.rst

@@ -3,9 +3,11 @@ The plugin API
 
 .. currentmodule:: jedi
 
+Note: This documentation is for Plugin developers, who want to improve their
+editors/IDE autocompletion 
+
 If you want to set up an editor/IDE-plugin with **Jedi**, you first need to
-``import jedi``. You then have direct access to the :class:`.Script`,
-:class:`.NotFoundError` and :func:`.set_debug_function` objects.
+``import jedi``. You then have direct access to the :class:`.Script`.
 
 
 API documentation