diff --git a/dotfiles/lib/shellrc/yelp.sh b/dotfiles/lib/shellrc/yelp.sh
index 6d3c9efa..8b967dae 100644
--- a/dotfiles/lib/shellrc/yelp.sh
+++ b/dotfiles/lib/shellrc/yelp.sh
@@ -51,7 +51,7 @@ function sandbox_prompt_info() {
     if [ "$YELP_IN_SANDBOX" ];
     then
         sandbox_string=$sandbox_string"sandbox-$(get_sandbox_identifier)"
-    elif [ ! -z $(env | grep YELP) ];
+    elif [ ! -z "$(env | grep yelp | head)" ] && git branch 1>/dev/null 2>/dev/null;
     then
         sandbox_string="no sandbox"
     fi
diff --git a/dotfiles/lib/zsh/prompt.sh b/dotfiles/lib/zsh/prompt.sh
index f7f6b9a6..391e6ae0 100644
--- a/dotfiles/lib/zsh/prompt.sh
+++ b/dotfiles/lib/zsh/prompt.sh
@@ -22,7 +22,7 @@ function git_status_character() {
 }
 
 function sandbox_prompt() {
-    if [ ! -z $(sandbox_prompt_info) ];
+    if [ ! -z "$(sandbox_prompt_info)" ];
     then
         echo " %{$FG[239]%}with $(colored_sandbox_string)%{$reset_color%}"
     fi