Add docstring warning

Author: bdowning

README.md

@@ -4,6 +4,9 @@ Python tool for slicing and dicing SQL.  Its intended target is
 Postgres with _asyncpg_, though it also includes support for rendering
 to a SQLAlchemy `TextClause`.
 
+_Note that current docstrings are autogenerated and have not been
+carefully reviewed; take them with a grain of salt!_
+
 ## Base query builder
 
 ### Example