diff --git a/src/archive.js b/src/archive.js
index c9f332c..76816a0 100644
--- a/src/archive.js
+++ b/src/archive.js
@@ -38,7 +38,7 @@ class Archive {
 	/**
 	 * Open an archive
 	 * @param  {binary} input
-	 * @param  {boolean} isBase64 tells JSZip if the input data is base64 encoded
+	 * @param  {boolean} [isBase64] tells JSZip if the input data is base64 encoded
 	 * @return {Promise} zipfile
 	 */
 	open(input, isBase64){
@@ -48,7 +48,7 @@ class Archive {
 	/**
 	 * Load and Open an archive
 	 * @param  {string} zipUrl
-	 * @param  {boolean} isBase64 tells JSZip if the input data is base64 encoded
+	 * @param  {boolean} [isBase64] tells JSZip if the input data is base64 encoded
 	 * @return {Promise} zipfile
 	 */
 	openUrl(zipUrl, isBase64){
@@ -62,7 +62,7 @@ class Archive {
 	 * Request a url from the archive
 	 * @param  {string} url  a url to request from the archive
 	 * @param  {string} [type] specify the type of the returned result
-	 * @return {Promise}
+	 * @return {Promise<Blob | string | JSON | Document | XMLDocument>}
 	 */
 	request(url, type){
 		var deferred = new defer();
diff --git a/src/layout.js b/src/layout.js
index 8b0ebec..46cbfc1 100644
--- a/src/layout.js
+++ b/src/layout.js
@@ -8,7 +8,7 @@ import EventEmitter from "event-emitter";
  * @param {object} settings
  * @param {string} [settings.layout='reflowable']
  * @param {string} [settings.spread]
- * @param {int} [settings.minSpreadWidth=800]
+ * @param {number} [settings.minSpreadWidth=800]
  * @param {boolean} [settings.evenSpreads=false]
  */
 class Layout {
@@ -55,6 +55,7 @@ class Layout {
 	/**
 	 * Switch the flow between paginated and scrolled
 	 * @param  {string} flow paginated | scrolled
+	 * @return {string} simplified flow
 	 */
 	flow(flow) {
 		if (typeof(flow) != "undefined") {
@@ -74,8 +75,9 @@ class Layout {
 	/**
 	 * Switch between using spreads or not, and set the
 	 * width at which they switch to single.
-	 * @param  {string} spread true | false
-	 * @param  {boolean} min integer in pixels
+	 * @param  {string} spread "none" | "always" | "auto"
+	 * @param  {number} min integer in pixels
+	 * @return {boolean} spread true | false
 	 */
 	spread(spread, min) {
 
@@ -94,9 +96,9 @@ class Layout {
 
 	/**
 	 * Calculate the dimensions of the pagination
-	 * @param  {number} _width  [description]
-	 * @param  {number} _height [description]
-	 * @param  {number} _gap    [description]
+	 * @param  {number} _width  width of the rendering
+	 * @param  {number} _height height of the rendering
+	 * @param  {number} _gap    width of the gap between columns
 	 */
 	calculate(_width, _height, _gap){
 
@@ -231,6 +233,11 @@ class Layout {
 
 	}
 
+	/**
+	 * Update props that have changed
+	 * @private
+	 * @param  {object} props
+	 */
 	update(props) {
 		// Remove props that haven't changed
 		Object.keys(props).forEach((propName) => {
diff --git a/src/utils/queue.js b/src/utils/queue.js
index f04d2e5..1f8a18a 100644
--- a/src/utils/queue.js
+++ b/src/utils/queue.js
@@ -181,7 +181,7 @@ class Queue {
 
 	/**
 	 * Get the number of tasks in the queue
-	 * @return {int} tasks
+	 * @return {number} tasks
 	 */
 	length(){
 		return this._q.length;
diff --git a/src/utils/url.js b/src/utils/url.js
index e8d1a4d..1c7739f 100644
--- a/src/utils/url.js
+++ b/src/utils/url.js
@@ -73,6 +73,7 @@ class Url {
 
 	/**
 	 * Resolves a relative path to a absolute url
+	 * @param {string} what
 	 * @returns {string} url
 	 */
 	resolve (what) {
@@ -89,6 +90,7 @@ class Url {
 
 	/**
 	 * Resolve a path relative to the url
+	 * @param {string} what
 	 * @returns {string} path
 	 */
 	relative (what) {