I noticed that there are EntryClickedEvent and commandToRunOnFirstRead.
It would be even better if there was another event fired when a entry is first read.

@Karashok-Leo I will add this presently. Please make sure to read the (brief) documentation on the event regarding providing rewards or doing persistent game logic, as the event is not (fully) guaranteed to run only once per entry.

To summarize, if you use the event for rewards, you should store distributed rewards in a savegame to ensure players cannot "double dip".