diff --git a/gmime/GMime-3.0.metadata b/gmime/GMime-3.0.metadata
index 46c4a6d1..3497be81 100644
--- a/gmime/GMime-3.0.metadata
+++ b/gmime/GMime-3.0.metadata
@@ -30,3 +30,7 @@ Object
   .write_to_stream#virtual_method name="write_to_stream_vfunc"
 FilterBest
   .charset#method name="get_charset"
+
+// Reparenting
+Stream
+  .buffer_* parent="GMime.StreamBuffer" name="buffer_(.+)"
diff --git a/gmime/gmime-stream-buffer.c b/gmime/gmime-stream-buffer.c
index 0bc82371..aae940f0 100644
--- a/gmime/gmime-stream-buffer.c
+++ b/gmime/gmime-stream-buffer.c
@@ -518,7 +518,7 @@ g_mime_stream_buffer_new (GMimeStream *source, GMimeStreamBufferMode mode)
 /**
  * g_mime_stream_buffer_gets:
  * @stream: stream
- * @buf: line buffer
+ * @buf: (array length=max) (element-type guint8): line buffer
  * @max: max length of a line
  *
  * Reads in at most one less than @max characters from @stream and
diff --git a/gmime/gmime-stream.c b/gmime/gmime-stream.c
index 3127b969..cae99fcb 100644
--- a/gmime/gmime-stream.c
+++ b/gmime/gmime-stream.c
@@ -190,7 +190,7 @@ stream_write (GMimeStream *stream, const char *buf, size_t len)
 /**
  * g_mime_stream_write:
  * @stream: a #GMimeStream
- * @buf: buffer
+ * @buf: (array length=len) (element-type guint8): buffer
  * @len: buffer length
  *
  * Attempts to write up to @len bytes of @buf to @stream.
@@ -573,7 +573,7 @@ g_mime_stream_write_to_stream (GMimeStream *src, GMimeStream *dest)
 /**
  * g_mime_stream_writev:
  * @stream: a #GMimeStream
- * @vector: a #GMimeStreamIOVector
+ * @vector: (array length=count): a #GMimeStreamIOVector
  * @count: number of vector elements
  *
  * Writes at most @count blocks described by @vector to @stream.