Possible to up complete passive skill?
 

im re-spec quite often
is this possible by API or not - to levelup passive skill in one click, without clicking for each level of it?

Yes, you can use the function:

with the following caveats:

• putPointInNextUpgrade should be false for purchasing the initial passive (current level is 0) and then true for subsequent purchases.
• There is a limit on how fast/often you can call this function before you get kicked for spamming. For example, when I'm mining skills and purchase one level of all passives I have to spread out the calls over around 30 seconds, and even then sometimes the game doesn't like it.