diff --git a/README.md b/README.md
index f4ada07..67873bf 100644
--- a/README.md
+++ b/README.md
@@ -36,6 +36,8 @@ moq [flags] source-dir interface [interface2 [interface3 [...]]]
 		go pretty-printer: gofmt, goimports or noop (default gofmt)
 	-out string
 		output file (default stdout)
+	-out-dir string
+		output dir (exclusive with -out)
 	-pkg string
 		package name (default will infer)
 	-stub
diff --git a/main.go b/main.go
index 48fb22c..1699d95 100644
--- a/main.go
+++ b/main.go
@@ -93,7 +93,7 @@ func run(flags userFlags) error {
 
 	switch {
 	case flags.outDir != "" && flags.outFile != "":
-		return errors.New("use only one from -out and -out-dir arguments")
+		return errors.New("use only one  of the flags -out and -out-dir")
 	case flags.outDir != "":
 		return mockToDir(m, flags.outDir, args...)
 	case flags.outFile != "":