diff --git a/relay/adaptor/gemini/main.go b/relay/adaptor/gemini/main.go
index e006c594..8b934d30 100644
--- a/relay/adaptor/gemini/main.go
+++ b/relay/adaptor/gemini/main.go
@@ -172,11 +172,16 @@ func getToolCalls(candidate *ChatCandidate) []model.Tool {
 	if item.FunctionCall == nil {
 		return toolCalls
 	}
+	argsBytes, err := json.Marshal(item.FunctionCall.Arguments)
+	if err != nil {
+		logger.FatalLog("getToolCalls failed: " + err.Error())
+		return toolCalls
+	}
 	toolCall := model.Tool{
 		Id:   fmt.Sprintf("call_%s", random.GetUUID()),
 		Type: "function",
 		Function: model.Function{
-			Arguments: item.FunctionCall.Arguments,
+			Arguments: string(argsBytes),
 			Name:      item.FunctionCall.FunctionName,
 		},
 	}
@@ -199,11 +204,15 @@ func responseGeminiChat2OpenAI(response *ChatResponse) *openai.TextResponse {
 			},
 			FinishReason: constant.StopFinishReason,
 		}
-		if candidate.Content.Parts[i].FunctionCall != nil {
-			choice.Message.ToolCalls = getToolCalls(&candidate)
-		} else if len(candidate.Content.Parts) > 0 {
-			choice.Message.Content = candidate.Content.Parts[i].Text
-
+		if len(candidate.Content.Parts) > 0 {
+			if candidate.Content.Parts[0].FunctionCall != nil {
+				choice.Message.ToolCalls = getToolCalls(&candidate)
+			} else {
+				choice.Message.Content = candidate.Content.Parts[0].Text
+			}
+		} else {
+			choice.Message.Content = ""
+			choice.FinishReason = candidate.FinishReason
 		}
 		fullTextResponse.Choices = append(fullTextResponse.Choices, choice)
 	}