We've recently created a template for user stories, and I'm trying to use automation to update the description of all existing user stories to match the new format. This will likely be a bit complex automation and take a few steps, but the first step is just to add to/edit the existing story a word. As a test, I created a test story and am trying to edit it with the code below (note, I don't really know JSON, but have had some guidance):

I don't believe the description field needs brackets, but if I put brackets around it like below, the error goes away, but I get a runtime error:


It seems it does not like the description field in the update section, however, this snippet of code is in atlassian doc.
Advanced field editing - JSON | Jira Software Cloud | Atlassian Support

So, it would appear that this should be possible, if it is in their doc. Hoping someone can provide some help and guidance!
Erich