code: func (a *Agent) InstallKey(key, token string, relayFactor uint8) (*structs.KeyringResponses, error) {
  	args := structs.KeyringRequest{Key: key, Operation: structs.KeyringInstall}
  	parseKeyringRequest(&args, token, relayFactor)
  	return a.keyringProcess(&args)
  }
docs: // InstallKey installs a new gossip encryption key