diff --git a/Lib/asyncio/runners.py b/Lib/asyncio/runners.py
index 6c87747..904102b 100644
--- a/Lib/asyncio/runners.py
+++ b/Lib/asyncio/runners.py
@@ -21,6 +21,10 @@
     It should be used as a main entry point for asyncio programs, and should
     ideally only be called once.
 
+    Return a result of *coro* execution, or raise a RuntimeError
+    if `asyncio.run()`is called from a running event loop, or a ValueError
+    if `main` is not a courutine.
+
     Example:
 
         async def main():