Really good game! I have a few suggestions to streamline the game a bit more:
1. Making it so that any iteration of a spy's Call Sign (for example. Nova) able to be searched in all iterations of upper case or lowercase. My first playthrough, I was a bit stuck on the Call Signs because I was using all lowercase. I was going through the comments to see what was wrong before capitalizing the first letter, in which it worked. I just think it would make it easier for players in general to have it uppercase or lowercase in general.
2. A tutorial. I know you've seen the other comments on it, but without a tutorial, it's not giving the players a chance to get it right the first run.
3. Maybe, after the tutorial, have an option in a menu to recap the tutorial, or have an in game little pamphlet going over the main things again.
Overall, I really enjoyed this game! I would like it if i didnt have to scroll through the comments and description to find the controls and instructions though. You've got a really fun game here!