diff --git a/core/coreunix/add.go b/core/coreunix/add.go
index df591574d..32aaca4ac 100644
--- a/core/coreunix/add.go
+++ b/core/coreunix/add.go
@@ -67,6 +67,8 @@ func AddR(n *core.IpfsNode, root string) (key string, err error) {
 
 // AddWrapped adds data from a reader, and wraps it with a directory object
 // to preserve the filename.
+// Returns the path of the added file ("<dir hash>/filename"), the DAG node of
+// the directory, and and error if any.
 func AddWrapped(n *core.IpfsNode, r io.Reader, filename string) (string, *merkledag.Node, error) {
 	file := files.NewReaderFile(filename, ioutil.NopCloser(r), nil)
 	dir := files.NewSliceFile("", []files.File{file})