class Net::SSH::Authentication::KeyManager

def use_agent=(use_agent)

connection to an agent is closed and the agent will not be used.
attempt will be made to use the ssh-agent. If false, any existing
Toggles whether the ssh-agent will be used or not. If true, an 
def use_agent=(use_agent)
  finish if !use_agent
  @use_agent = use_agent
end