diff --git a/proxy/proto.go b/proxy/proto.go
index 1c81d3c89..dab1b2a55 100644
--- a/proxy/proto.go
+++ b/proxy/proto.go
@@ -31,7 +31,7 @@ type JSONRpcResp struct {
 	Id      json.RawMessage `json:"id"`
 	Version string          `json:"jsonrpc,omitempty"`
 	Result  interface{}     `json:"result"`
-	Error   interface{}     `json:"error,omitempty"`
+	Error   interface{}     `json:"error"`
 }
 
 type SubmitReply struct {