diff --git a/cli/auth.go b/cli/auth.go
index 2f41b38d1..8723b1576 100644
--- a/cli/auth.go
+++ b/cli/auth.go
@@ -90,7 +90,7 @@ var authApiInfoToken = &cli.Command{
 		ctx := ReqContext(cctx)
 
 		if !cctx.IsSet("perm") {
-			return xerrors.New("--perm flag not set")
+			return xerrors.New("--perm flag not set, use with one of: read, write, sign, admin")
 		}
 
 		perm := cctx.String("perm")