Limits to building a local database from scratch

When Cyd builds its local database of your tweets, it learns your tweet history the same way you would: By loading your profile to see your tweets, then scrolling down over and over until it gets to the bottom. Unfortunately, X appears to only show you about between 2,000 and 3,000 of your most recent tweets (and likes) in this way.

After you delete all of those, X simply won't show you any of your tweet history on your profile page anymore, even if you have thousands of older tweets.

Cyd needs a local database in order to delete your tweets and likes. If you don't have all that many tweets or likes, this is a perfectly fine way to create your local database. But if your account has a lot of data, you should import data from an X archive instead.