diff --git a/direnvrc b/direnvrc
index ec29415..3ddfbea 100644
--- a/direnvrc
+++ b/direnvrc
@@ -195,6 +195,14 @@ use_flake() {
   flake_expr="${1:-.}"
   flake_dir="${flake_expr%#*}"
 
+  if [[ "$flake_expr" =~ ^-[^#]*$ ]]; then
+    if [[ -n "$2" ]]; then
+      log_status "nix-direnv: the first argument must be a flake expression"
+    else
+      log_status "nix-direnv: the first argument must be a flake expression. did you mean 'use flake . $1'?"
+    fi
+  fi
+
   local files_to_watch
   files_to_watch=(".envrc" "$HOME/.direnvrc" "$HOME/.config/direnv/direnvrc")