diff --git a/lib/internal/validators.js b/lib/internal/validators.js
index a5e5676db7dc3e..0f0933de41a631 100644
--- a/lib/internal/validators.js
+++ b/lib/internal/validators.js
@@ -36,7 +36,7 @@ const { signals } = internalBinding('constants').os;
 
 /**
  * @param {*} value
- * @returns {boolean}
+ * @returns {value is number}
  */
 function isInt32(value) {
   return value === (value | 0);
@@ -44,7 +44,7 @@ function isInt32(value) {
 
 /**
  * @param {*} value
- * @returns {boolean}
+ * @returns {value is number}
  */
 function isUint32(value) {
   return value === (value >>> 0);
@@ -291,6 +291,7 @@ function validateSignalName(signal, name = 'signal') {
  * @callback validateBuffer
  * @param {*} buffer
  * @param {string} [name='buffer']
+ * @returns {asserts buffer is ArrayBufferView}
  */
 
 /** @type {validateBuffer} */