diff --git a/plugins/wasm-go/extensions/ai-proxy/main.go b/plugins/wasm-go/extensions/ai-proxy/main.go
index 4a2d1fb98c..92ec3940f3 100644
--- a/plugins/wasm-go/extensions/ai-proxy/main.go
+++ b/plugins/wasm-go/extensions/ai-proxy/main.go
@@ -15,6 +15,7 @@ import (
 	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
 	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
 	"github.com/tidwall/gjson"
+	"github.com/tidwall/sjson"
 )
 
 const (
@@ -149,7 +150,14 @@ func onHttpRequestBody(ctx wrapper.HttpContext, pluginConfig config.PluginConfig
 			)
 			return types.ActionContinue
 		}
-
+		// Default setting include_usage.
+		if gjson.GetBytes(body, "stream").Bool() {
+			var err error
+			newBody, err = sjson.SetBytes(newBody, "stream_options.include_usage", true)
+			if err != nil {
+				log.Errorf("set include_usage failed, err:%s", err)
+			}
+		}
 		log.Debugf("[onHttpRequestBody] newBody=%s", newBody)
 		body = newBody
 		action, err := handler.OnRequestBody(ctx, apiName, body, log)
diff --git a/plugins/wasm-go/extensions/ai-proxy/provider/openai.go b/plugins/wasm-go/extensions/ai-proxy/provider/openai.go
index 2def57aa62..f875dbaa40 100644
--- a/plugins/wasm-go/extensions/ai-proxy/provider/openai.go
+++ b/plugins/wasm-go/extensions/ai-proxy/provider/openai.go
@@ -127,21 +127,14 @@ func (m *openaiProvider) OnRequestBody(ctx wrapper.HttpContext, apiName ApiName,
 }
 
 func (m *openaiProvider) TransformRequestBody(ctx wrapper.HttpContext, apiName ApiName, body []byte, log wrapper.Log) ([]byte, error) {
-	request := &chatCompletionRequest{}
-	if err := decodeChatCompletionRequest(body, request); err != nil {
-		return nil, err
-	}
 	if m.config.responseJsonSchema != nil {
+		request := &chatCompletionRequest{}
+		if err := decodeChatCompletionRequest(body, request); err != nil {
+			return nil, err
+		}
 		log.Debugf("[ai-proxy] set response format to %s", m.config.responseJsonSchema)
 		request.ResponseFormat = m.config.responseJsonSchema
+		body, _ = json.Marshal(request)
 	}
-	if request.Stream {
-		// For stream requests, we need to include usage in the response.
-		if request.StreamOptions == nil {
-			request.StreamOptions = &streamOptions{IncludeUsage: true}
-		} else if !request.StreamOptions.IncludeUsage {
-			request.StreamOptions.IncludeUsage = true
-		}
-	}
-	return json.Marshal(request)
+	return m.config.defaultTransformRequestBody(ctx, apiName, body, log)
 }