Quick Summary: The key authenticated, but it was not granted the scope this operation requires.
detail names the missing scope. Fix: an administrator grants it under Settings → API Credentials — it takes effect on the very next call.What happened
Every operation declares the scope it requires (shown as Requires scope on its reference page). This key’s scope list does not include it. The request was refused at the scope gate — before any data was read or any permission of the acting person was evaluated.What to do
Grant the named scope to the key. Note that:write never implies :read — grant both if you need both. Nothing about the acting person needs to change for this error.
Not the same as insufficient-permissions
If the key does hold the scope but the person it acts as is not allowed to perform the operation, you get insufficient-permissions instead — and granting scopes will not fix that one. The two are separate problem types precisely so your error handling can branch on type rather than parse detail.