diff --git a/lib/iterable-to-string.js b/lib/iterable-to-string.js
index a5405d5..b8b0c70 100644
--- a/lib/iterable-to-string.js
+++ b/lib/iterable-to-string.js
@@ -4,6 +4,13 @@ var slice = require("@sinonjs/commons").prototypes.string.slice;
 var typeOf = require("@sinonjs/commons").typeOf;
 var valueToString = require("@sinonjs/commons").valueToString;
 
+/**
+ * Creates a string represenation of an iterable object
+ *
+ * @private
+ * @param   {object} obj The iterable object to stringify
+ * @returns {string}     A string representation
+ */
 function iterableToString(obj) {
     if (typeOf(obj) === "map") {
         return mapToString(obj);
@@ -12,6 +19,13 @@ function iterableToString(obj) {
     return genericIterableToString(obj);
 }
 
+/**
+ * Creates a string representation of a Map
+ *
+ * @private
+ * @param   {Map} map    The map to stringify
+ * @returns {string}     A string representation
+ */
 function mapToString(map) {
     var representation = "";
 
@@ -24,6 +38,13 @@ function mapToString(map) {
     return representation;
 }
 
+/**
+ * Create a string represenation for an iterable
+ *
+ * @private
+ * @param   {object} iterable The iterable to stringify
+ * @returns {string}          A string representation
+ */
 function genericIterableToString(iterable) {
     var representation = "";
 
@@ -36,6 +57,13 @@ function genericIterableToString(iterable) {
     return representation;
 }
 
+/**
+ * Creates a string representation of the passed `item`
+ *
+ * @private
+ * @param  {object} item The item to stringify
+ * @returns {string}      A string representation of `item`
+ */
 function stringify(item) {
     return typeof item === "string" ? "'" + item + "'" : valueToString(item);
 }