Error while saving workitem with Rich text content in description via java script

We have a java script automation that creates a child work item of the parent work item. When the parent description has a rich text content and try to copy to the child wi, we are facing the following error on save of the work items having Rich Text description,

Could not save work item : CRRTC0300E: The work item with the ID <id> cannot be saved because this client version cannot modify extended rich text content in the attributes '[Description]'. To modify an attribute that contains extended rich text use the web client.

Is it so that the Rich Text cannot be added or modified by any client except via the Web browser itself?

We are here using  java script api call  service provided by RTC(which is almost similar to the call made by the web). Below is the snippet :

this.createWorkItem = function (workItemCopy, completeWorkItemSummary, owner, dueDate, category, target, spawnWorkItemType,description) {
var projectAreaHandle = workItemCopy.getProjectArea();
var newWorkItem = Api.WorkItems.createWorkItemByAreaHandleAndTypeId(projectAreaHandle, spawnWorkItemType, completeWorkItemSummary);



if (owner != null) {
newWorkItem.setOwner(owner);
}

if (dueDate != null) {
newWorkItem.setDueDate(dueDate);
}

if (category != null) {
newWorkItem.setCategory(category);
}

if (target != null) {
newWorkItem.setTarget(target);
}
newWorkItem.setDescription(description);

return Api.WorkItems.commitWorkItem(newWorkItem);
};