diff --git a/glib/gchecksum.c b/glib/gchecksum.c
index 40b1d50e2..f151ced49 100644
--- a/glib/gchecksum.c
+++ b/glib/gchecksum.c
@@ -1682,8 +1682,8 @@ g_checksum_get_string (GChecksum *checksum)
 /**
  * g_checksum_get_digest: (skip)
  * @checksum: a #GChecksum
- * @buffer: output buffer
- * @digest_len: an inout parameter. The caller initializes it to the size of @buffer.
+ * @buffer: (array length=digest_len): output buffer
+ * @digest_len: (inout): an inout parameter. The caller initializes it to the size of @buffer.
  *   After the call it contains the length of the digest.
  *
  * Gets the digest from @checksum as a raw binary vector and places it
diff --git a/glib/ghmac.c b/glib/ghmac.c
index 9b58fd81c..af9b6744a 100644
--- a/glib/ghmac.c
+++ b/glib/ghmac.c
@@ -300,8 +300,8 @@ g_hmac_get_string (GHmac *hmac)
 /**
  * g_hmac_get_digest:
  * @hmac: a #GHmac
- * @buffer: output buffer
- * @digest_len: an inout parameter. The caller initializes it to the
+ * @buffer: (array length=digest_len): output buffer
+ * @digest_len: (inout): an inout parameter. The caller initializes it to the
  *   size of @buffer. After the call it contains the length of the digest
  *
  * Gets the digest from @checksum as a raw binary array and places it