In order to develop new client-side web parts using the SharePoint Framework (SPFx) preview, you will need the following correctly setup:
- An Office 365 Developer Tenant (note that it must be a developer tenant via the Office Dev Program)
- A working App Catalog site in your tenant
- A developer site collection
- An uploaded workbench.aspx file to the library
- A site column in your “Documents” document library called “ClientSideApplicationId“
If you try to browse to your site (i.e. https://mytenant.sharepoint.com/sites/dev/Shared%20Documents/workbench.aspx) and miss or forget step #5 , you will get the following error:
Sorry,
something went wrong
something went wrong
‘ClientSideApplicationId’ does not exists in list or list item
All of these instructions can be found here.