diff --git a/lib/rule-tester/flat-rule-tester.js b/lib/rule-tester/flat-rule-tester.js
index f297965ec33b..fcbf845d9139 100644
--- a/lib/rule-tester/flat-rule-tester.js
+++ b/lib/rule-tester/flat-rule-tester.js
@@ -32,6 +32,7 @@ const { ConfigArraySymbol } = require("@humanwhocodes/config-array");
 
 /** @typedef {import("../shared/types").Parser} Parser */
 /** @typedef {import("../shared/types").LanguageOptions} LanguageOptions */
+/** @typedef {import("../shared/types").Rule} Parser */
 
 
 /**
@@ -446,7 +447,7 @@ class FlatRuleTester {
     /**
      * Adds a new rule test to execute.
      * @param {string} ruleName The name of the rule to run.
-     * @param {Function} rule The rule to test.
+     * @param {Function | Rule} rule The rule to test.
      * @param {{
      *   valid: (ValidTestCase | string)[],
      *   invalid: InvalidTestCase[]