diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index 89a857f50..1748315bc 100644
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh
@@ -175,7 +175,6 @@ list_merge_tool_candidates () {
 }
 
 show_tool_help () {
-	TOOL_MODE=merge
 	list_merge_tool_candidates
 	unavailable= available= LF='
 '