Share Secret Messages with Specific Users

I've built a tool that works as follows:

1. Sign in with Twitter.

2. Type out the intended Twitter usernames (as many as you like) along with your secret messages.

3. The tool generates a common link and shares it on Twitter, tagging all the intended users to get notified.

4. When the intended users click on the link, it performs a Twitter authentication check to grant access to the messages.

5. If someone other than the intended users clicks on the link, it displays a message saying 'you are unauthorized to have access to this message.'

Is it Twitter privacy violation?

If not suggest me a practical usecase!