diff --git a/doc/error_codes.md b/doc/error_codes.md
index e127e7d6e7d85f9ffa9bd7207446dfd8b22add99..49cb084ee4593b68d06668a631cc1fa367c94bec 100644
--- a/doc/error_codes.md
+++ b/doc/error_codes.md
@@ -1,7 +1,7 @@
 * 0: OK
 * 1: Generic error
-* 10: Init failed because $GIT_DIR exists
-* 11: Could not enter $GIT_WORK_TREE
+* 10: Init failed because $GIT\_DIR exists
+* 11: Could not enter $GIT\_WORK\_TREE
 * 12: No repository found
 * 13: Required directory exists but is not a directory
 * 16: Potentially harmful operation aborted