addShard
What changes in addShard compared with MongoDB and what your application has to do.
This difference is of the Different kind.
What MongoDB does
addShard connects to the replica set you give it and adds it.
What TeselaDB does
With the address of a node outside the cluster it fails with OperationFailed and explains that the node joins with its enrolment token. With the address of a node in the cluster it answers with its name.
What your application has to do
Add nodes with teseladb admin token create and --join, not with addShard.