Zephyr Enterprise REST API not finished?

I'm trying to update the status of some test steps via the REST API, I can bulk update testcases and include the test steps with "teststepUpdate" so they will all PASS/FAIL with execute-testcases. However there is no data or examples for update-test-step-result, looking over them there are many API methods listed with no data in the methods, I even found TODOs here. Is the API still mid development?