routespreferred/v1/routespreferred_grpc_service_config.json

{
  "methodConfig": [{
    "name": [{ "service": "google.maps.routespreferred.v1.RoutesPreferred" }],
    "timeout": "30s",
    "retryPolicy": {
      "maxAttempts": 5,
      "initialBackoff": "1s",
      "maxBackoff": "30s",
      "backoffMultiplier": 1.3,
      "retryableStatusCodes": ["UNAVAILABLE"]
    }
  }
 ]
}