diff --git a/docs/development/CUSTOM_RULES.md b/docs/development/CUSTOM_RULES.md
index f41cd7b72ca6..a101dadbd297 100644
--- a/docs/development/CUSTOM_RULES.md
+++ b/docs/development/CUSTOM_RULES.md
@@ -277,9 +277,13 @@ const ruleTester = new ESLintUtils.RuleTester({
   parser: '@typescript-eslint/parser',
 });
 
-ruleTester.run('my-rule', rule {
-  valid: [/* ... */],
-  invalid: [/* ... */],
+ruleTester.run('my-rule', rule, {
+  valid: [
+    /* ... */
+  ],
+  invalid: [
+    /* ... */
+  ],
 });
 ```