diff --git a/plugins/wasm-go/extensions/ai-proxy/provider/bedrock.go b/plugins/wasm-go/extensions/ai-proxy/provider/bedrock.go
index 4e84a758a..034c78ea9 100644
--- a/plugins/wasm-go/extensions/ai-proxy/provider/bedrock.go
+++ b/plugins/wasm-go/extensions/ai-proxy/provider/bedrock.go
@@ -107,9 +107,8 @@ func (b *bedrockProvider) convertEventFromBedrockToOpenAI(ctx wrapper.HttpContex
 		chatChoice.Delta.Content = nil
 		chatChoice.Delta.ToolCalls = []toolCall{
 			{
-				Id:    bedrockEvent.Start.ToolUse.ToolUseID,
-				Index: 0,
-				Type:  "function",
+				Id:   bedrockEvent.Start.ToolUse.ToolUseID,
+				Type: "function",
 				Function: functionCall{
 					Name:      bedrockEvent.Start.ToolUse.Name,
 					Arguments: "",
@@ -138,8 +137,7 @@ func (b *bedrockProvider) convertEventFromBedrockToOpenAI(ctx wrapper.HttpContex
 		if bedrockEvent.Delta.ToolUse != nil {
 			chatChoice.Delta.ToolCalls = []toolCall{
 				{
-					Index: 0,
-					Type:  "function",
+					Type: "function",
 					Function: functionCall{
 						Arguments: bedrockEvent.Delta.ToolUse.Input,
 					},
@@ -168,7 +166,6 @@ func (b *bedrockProvider) convertEventFromBedrockToOpenAI(ctx wrapper.HttpContex
 			TotalTokens:      bedrockEvent.Usage.TotalTokens,
 		}
 	}
-
 	openAIFormattedChunkBytes, _ := json.Marshal(openAIFormattedChunk)
 	var openAIChunk strings.Builder
 	openAIChunk.WriteString(ssePrefix)
diff --git a/plugins/wasm-go/extensions/ai-proxy/provider/model.go b/plugins/wasm-go/extensions/ai-proxy/provider/model.go
index 630d18c3d..3a11a279b 100644
--- a/plugins/wasm-go/extensions/ai-proxy/provider/model.go
+++ b/plugins/wasm-go/extensions/ai-proxy/provider/model.go
@@ -393,7 +393,7 @@ func (m *chatMessage) ParseContent() []chatMessageContent {
 }
 
 type toolCall struct {
-	Index    int          `json:"index,omitempty"`
+	Index    int          `json:"index"`
 	Id       string       `json:"id,omitempty"`
 	Type     string       `json:"type"`
 	Function functionCall `json:"function"`