diff --git a/Doc/c-api/arg.rst b/Doc/c-api/arg.rst
index 8fbdc50..61fe937 100644
--- a/Doc/c-api/arg.rst
+++ b/Doc/c-api/arg.rst
@@ -136,7 +136,8 @@
    :c:func:`PyArg_ParseTuple` will use this location as the buffer and
    interpret the initial value of *\*buffer_length* as the buffer size.  It
    will then copy the encoded data into the buffer and NUL-terminate it.  If
-   the buffer is not large enough, a :exc:`ValueError` will be set.
+   the buffer is not large enough, a :exc:`TypeError` will be set.
+   Note: starting from Python 3.6 a :exc:`ValueError` will be set.
 
    In both cases, *\*buffer_length* is set to the length of the encoded data
    without the trailing NUL byte.