for example: in dungen,have two tank,I need to get who is the first and who is the second, do rb have this api?
Rb does have an extensive api but it is lacking functions for threat list because the data is not stored in the client. The game does not store threat information for any units except the one currently being targeted.
You say it doesn't matter, but it does. Adding an api for threat would then require that we know if the threat data we have for the current target is stale, how long ago we switched targets etc. I'll take another look at it to see if it could be done cleanly, but I don't expect it will be.
This api can use to bring some new functions that never dev before,really need this. For example: in Savage dungen,Tank and healer could basis this to use appoint skills