diff --git a/doc/internals/buffer-api.txt b/doc/internals/buffer-api.txt
index 13881f7..abb5e9f 100644
--- a/doc/internals/buffer-api.txt
+++ b/doc/internals/buffer-api.txt
@@ -568,10 +568,10 @@
                     |                  | even if some memory is available
 --------------------+------------------+---------------------------------------
 __b_drop            | buffer *buf      | releases <buf> which must be allocated
-                    | ret: void        |
+                    | ret: void        | and marks it empty
 --------------------+------------------+---------------------------------------
 b_drop              | buffer *buf      | releases <buf> only if it is allocated
-                    | ret: void        |
+                    | ret: void        | and marks it empty
 --------------------+------------------+---------------------------------------
 b_free              | buffer *buf      | releases <buf> only if it is allocated
                     | ret: void        | and marks it empty