diff --git a/platform/features/timeline/src/actions/CompositionColumn.js b/platform/features/timeline/src/actions/CompositionColumn.js
index 3fff0bda37..e33f028f99 100644
--- a/platform/features/timeline/src/actions/CompositionColumn.js
+++ b/platform/features/timeline/src/actions/CompositionColumn.js
@@ -27,6 +27,9 @@ define([], function () {
      * in a domain object's composition.
      * @param {number} index the zero-based index of the composition
      *        element associated with this column
+     * @param idMap an object containing key value pairs, where keys
+     *        are domain object identifiers and values are whatever
+     *        should appear in CSV output in their place
      * @constructor
      * @implements {platform/features/timeline.TimelineCSVColumn}
      */
diff --git a/platform/features/timeline/src/actions/IdColumn.js b/platform/features/timeline/src/actions/IdColumn.js
index b6ff15fe6c..9148ef6a8b 100644
--- a/platform/features/timeline/src/actions/IdColumn.js
+++ b/platform/features/timeline/src/actions/IdColumn.js
@@ -23,8 +23,11 @@
 define([], function () {
 
     /**
-     * A column showing domain object identifiers.
+     * A column showing identifying domain objects.
      * @constructor
+     * @param idMap an object containing key value pairs, where keys
+     *        are domain object identifiers and values are whatever
+     *        should appear in CSV output in their place
      * @implements {platform/features/timeline.TimelineCSVColumn}
      */
     function IdColumn(idMap) {
diff --git a/platform/features/timeline/src/actions/ModeColumn.js b/platform/features/timeline/src/actions/ModeColumn.js
index 26b307cbd0..05eec7a30a 100644
--- a/platform/features/timeline/src/actions/ModeColumn.js
+++ b/platform/features/timeline/src/actions/ModeColumn.js
@@ -27,6 +27,9 @@ define([], function () {
      * @constructor
      * @param {number} index the zero-based index of the composition
      *        element associated with this column
+     * @param idMap an object containing key value pairs, where keys
+     *        are domain object identifiers and values are whatever
+     *        should appear in CSV output in their place
      * @implements {platform/features/timeline.TimelineCSVColumn}
      */
     function ModeColumn(index, idMap) {