tempest is a library and tool for managing Riverbed Stingray Traffic Managers.
At the moment, the most useful thing it does is provide an interface for enabling, disabling and draining nodes.
The CLI tool understands a few different commands;
list - List pools
describe - Describe a pool
disable - Disable a node
drain - Drain a node
enable - Enable a node
help - Shows a list of commands or help for one command
Try "tempest help <command name>" for more information