code: func (command *CapnpCommand) Execute() error {
  	var apiDef raml.APIDefinition
  
  	command.Language = strings.ToLower(command.Language)
  	if command.Language != "go" && command.Language != "plain" {
  		return fmt.Errorf("canpnp generator only support plain & Go-compatible schema")
  	}
  
  	log.Debug("Generating capnp models")
  
  	err := raml.ParseFile(command.RAMLFile, &apiDef)
  	if err != nil {
  		return err
  	}
  	return codegen.GenerateCapnp(&apiDef, command.Dir, command.Language, command.Package)
  }
docs: //Execute generates a client from a RAML specification