diff --git a/js-lib/common.js b/js-lib/common.js
index e0ce8c2..0c2d312 100644
--- a/js-lib/common.js
+++ b/js-lib/common.js
@@ -23,7 +23,7 @@ ascii.Vector.prototype.equals = function(other) {
 
 /**
  * @param {ascii.Vector} other
- * @return {boolean}
+ * @return {ascii.Vector}
  */
 ascii.Vector.prototype.subtract = function(other) {
   return new ascii.Vector(this.x - other.x, this.y - other.y);
@@ -31,7 +31,7 @@ ascii.Vector.prototype.subtract = function(other) {
 
 /**
  * @param {ascii.Vector} other
- * @return {boolean}
+ * @return {ascii.Vector}
  */
 ascii.Vector.prototype.add = function(other) {
   return new ascii.Vector(this.x + other.x, this.y + other.y);
diff --git a/js-lib/state.js b/js-lib/state.js
index 69b35fa..24c816b 100644
--- a/js-lib/state.js
+++ b/js-lib/state.js
@@ -41,7 +41,7 @@ ascii.State = function() {
  * Returns the cell at the given coordinates.
  *
  * @param {ascii.Vector} vector
- * @return {asii.Cell}
+ * @return {ascii.Cell}
  */
 ascii.State.prototype.getCell = function(vector) {
   return this.cells[vector.x][vector.y];