diff --git a/lib/vector-util.js b/lib/vector-util.js
index ae5619f5..66165203 100644
--- a/lib/vector-util.js
+++ b/lib/vector-util.js
@@ -5,6 +5,21 @@
 'use strict';
 const { Buffer } = require('buffer');
 
+/**
+ * Provides functions to encode and decode vectors.
+ * MarkLogic 12 or higher needed.
+ * @namespace vectorUtil
+ */
+
+/**
+ * Converts an array of vector float values into an encoded string.
+ * Encoding vectors before writing them to documents in MarkLogic 12
+ * helps reduce the amount of disk space and memory consumed by vectors.
+ * @method vectorUtil#base64Encode
+ * @since 3.7.0
+ * @param {float[]}  vector - an array of float values
+ * @returns {string}  an encoded string value.
+ */
 const base64Encode = (vector) => {
     const dimensions = vector.length;
     const buffer = Buffer.alloc(8 + 4 * dimensions);
@@ -19,6 +34,13 @@ const base64Encode = (vector) => {
     return buffer.toString('base64');
 };
 
+/**
+ * Converts an encoded string value to an array of vectors.
+ * @method vectorUtil#base64Decode
+ * @since 3.7.0
+ * @param {string}  encodedVector - an encoded string value.
+ * @returns {float[]}  an array of float values.
+ */
 const base64Decode = (encodedVector) => {
 
     const buffer = Buffer.from(encodedVector, 'base64');