code: func (a *Agent) Stats() map[string]map[string]string {
  	stats := a.delegate.Stats()
  	stats["agent"] = map[string]string{
  		"check_monitors": strconv.Itoa(len(a.checkMonitors)),
  		"check_ttls":     strconv.Itoa(len(a.checkTTLs)),
  	}
  	for k, v := range a.State.Stats() {
  		stats["agent"][k] = v
  	}
  
  	revision := a.config.Revision
  	if len(revision) > 8 {
  		revision = revision[:8]
  	}
  	stats["build"] = map[string]string{
  		"revision":   revision,
  		"version":    a.config.Version,
  		"prerelease": a.config.VersionPrerelease,
  	}
  	return stats
  }
docs: // Stats is used to get various debugging state from the sub-systems