code: func (m *AgentPool) Counts() map[string]int {
  	out := make(map[string]int)
  
  	for key, agents := range m.agents {
  		out[key.tunnelID] += len(agents)
  	}
  
  	return out
  }
docs: // Counts returns a count of the number of proxies a outbound tunnel is
  // connected to. Used in tests to determine if a proxy has been found and/or
  // removed.