diff --git a/protocol/client_codec.go b/protocol/client_codec.go
index ecee9c5..e8d4f1a 100644
--- a/protocol/client_codec.go
+++ b/protocol/client_codec.go
@@ -22,7 +22,7 @@ type ClientCodecResponseOrNotify interface {
 
 type ClientCodecResponse interface {
 	ID() interface{}
-	Result() interface{}
+	Result(result interface{}) error
 	Error() error
 	Complete()
 }
diff --git a/protocol/json/client.go b/protocol/json/client.go
index 33f9f30..0d05df3 100644
--- a/protocol/json/client.go
+++ b/protocol/json/client.go
@@ -32,10 +32,10 @@ type clientRequest struct {
 
 // clientResponse represents a JSON-RPC response returned to a client.
 type clientResponse struct {
-	Version string      `json:"jsonrpc"`
-	Result  interface{} `json:"result,omitempty"`
-	Error   error       `json:"error,omitempty"`
-	ID      interface{} `json:"id"`
+	Version string           `json:"jsonrpc"`
+	Result  *json.RawMessage `json:"result,omitempty"`
+	Error   error            `json:"error,omitempty"`
+	ID      interface{}      `json:"id"`
 }
 
 // clientRequest represents a JSON-RPC request sent by a client.
diff --git a/protocol/json/client_response.go b/protocol/json/client_response.go
index b1d29db..4d4a3cd 100644
--- a/protocol/json/client_response.go
+++ b/protocol/json/client_response.go
@@ -47,8 +47,16 @@ func (ccr *ClientCodecResponse) ID() interface{} {
 	return ccr.response.ID
 }
 
-func (ccr *ClientCodecResponse) Result() interface{} {
-	return ccr.response.Result
+func (ccr *ClientCodecResponse) Result(result interface{}) error {
+	if ccr.err == nil && ccr.response.Result != nil {
+		if err := json.Unmarshal(*ccr.response.Result, result); err != nil {
+			params := [1]interface{}{result}
+			if err = json.Unmarshal(*ccr.response.Result, &params); err != nil {
+				ccr.err = err
+			}
+		}
+	}
+	return ccr.err
 }
 
 func (ccr *ClientCodecResponse) Error() error {