A Xots Tasklet must follow a few standard rules:
An org.openntf.domino.xots.XotsContext object is passed into the tasklet. This contains three properties:
If extending AbstractXspXotsCallable or AbstractXspXotsRunnable interfaces, an org.openntf.domino.xsp.xots.XotsXspContext object is passed, which has six additional properties:

If a Xots Tasklet is a Runnable the tasklet will run in the background and your code will continue.

If a Xots Tasklet is a Callable the tasklet returns a value and the code will wait for and process the response.