code: func (a *API) robot(res http.ResponseWriter, req *http.Request) {
  	if robot, err := a.jsonRobotFor(req.URL.Query().Get(":robot")); err != nil {
  		a.writeJSON(map[string]interface{}{"error": err.Error()}, res)
  	} else {
  		a.writeJSON(map[string]interface{}{"robot": robot}, res)
  	}
  }
docs: // robot returns route handler.
  // Writes JSON with robot representation