Wtf ?
If you're talking about the packet index when converting the packet to string definition, then it's very simple, and you have like 1000000000 examples in the code.
For example:
Walk 1 2 3 4
Walk: this is the packet header
1: PacketIndex 1
2: PacketIndex 2
...
Then you just have to try different stuff on the official servers to see what each index is made for.
If you can't even do that, good luck with the titles implementation. It's not hard, but it still requires some work