diff --git a/internal/runtime/executor/kimi_executor.go b/internal/runtime/executor/kimi_executor.go
index 7bf6078d..a3fe0f28 100644
--- a/internal/runtime/executor/kimi_executor.go
+++ b/internal/runtime/executor/kimi_executor.go
@@ -502,11 +502,10 @@ func moveKimiToolOutputImagesToUserMessages(body []byte) ([]byte, error) {
 }
 
 func splitKimiStructuredToolOutput(content gjson.Result) (string, []kimiToolOutputImage, bool) {
-	if content.Type != gjson.String {
-		return "", nil, false
+	structured := content
+	if content.Type == gjson.String {
+		structured = gjson.Parse(content.String())
 	}
-
-	structured := gjson.Parse(content.String())
 	var parts []gjson.Result
 	switch {
 	case structured.IsArray():
@@ -538,10 +537,11 @@ func splitKimiStructuredToolOutput(content gjson.Result) (string, []kimiToolOutp
 				textParts = append(textParts, part.Raw)
 				continue
 			}
-			images = append(images, kimiToolOutputImage{
-				url:    url,
-				detail: part.Get("detail").String(),
-			})
+			detail := part.Get("detail").String()
+			if detail == "" {
+				detail = part.Get("image_url.detail").String()
+			}
+			images = append(images, kimiToolOutputImage{url: url, detail: detail})
 			textParts = append(textParts, "[image output attached in the following user message]")
 		default:
 			textParts = append(textParts, part.Raw)
diff --git a/internal/runtime/executor/kimi_executor_test.go b/internal/runtime/executor/kimi_executor_test.go
index 125c8812..e6dd49ca 100644
--- a/internal/runtime/executor/kimi_executor_test.go
+++ b/internal/runtime/executor/kimi_executor_test.go
@@ -417,8 +417,8 @@ func TestKimiExecutorMovesResponsesToolImagesToNativeUserContentForBothExecution
 		if got := messages[3].Get("content.1.image_url.url").String(); got != imageURL {
 			t.Fatalf("request %d native image URL = %q, want %q", requestIndex, got, imageURL)
 		}
-		if got := messages[3].Get("content.1.image_url.detail").String(); got != "original" {
-			t.Fatalf("request %d native image detail = %q, want original", requestIndex, got)
+		if got := messages[3].Get("content.1.image_url.detail").String(); got != "high" {
+			t.Fatalf("request %d native image detail = %q, want high", requestIndex, got)
 		}
 		if got := messages[4].Get("content.0.text").String(); got != "next" {
 			t.Fatalf("request %d final user text = %q, want next", requestIndex, got)