diff --git a/core/block.js b/core/block.js
index 765437e19..5d4170ea9 100644
--- a/core/block.js
+++ b/core/block.js
@@ -79,6 +79,7 @@ Blockly.Block.obtain = function(workspace, prototypeName) {
  *     type-specific functions for this block.
  */
 Blockly.Block.prototype.initialize = function(workspace, prototypeName) {
+  /** @type {string} */
   this.id = Blockly.Blocks.genUid();
   workspace.addTopBlock(this);
   this.fill(workspace, prototypeName);
diff --git a/core/field.js b/core/field.js
index ee871b73c..7a4c38579 100644
--- a/core/field.js
+++ b/core/field.js
@@ -113,6 +113,7 @@ Blockly.Field.prototype.init = function(block) {
        'x': -Blockly.BlockSvg.SEP_SPACE_X / 2,
        'y': 0,
        'height': 16}, this.fieldGroup_, this.sourceBlock_.workspace);
+  /** @type {Element} */
   this.textElement_ = Blockly.createSvgElement('text',
       {'class': 'blocklyText', 'y': this.size_.height - 12.5}, this.fieldGroup_);