Fixed: #1670

test(translator): add unit tests for OpenAI to Claude requests and tool result handling

- Introduced tests for converting OpenAI requests to Claude with text, base64 images, and URL images in tool results.
- Refactored `convertClaudeToolResultContent` and related functionality to properly handle raw content with images and text.
- Updated conversion logic to streamline image handling for both base64 and URL formats.

internal/translator/openai/claude/openai_claude_request.go

@@ -183,7 +183,12 @@ func ConvertClaudeRequestToOpenAI(modelName string, inputRawJSON []byte, stream
 						// Collect tool_result to emit after the main message (ensures tool results follow tool_calls)
 						toolResultJSON := `{"role":"tool","tool_call_id":"","content":""}`
 						toolResultJSON, _ = sjson.Set(toolResultJSON, "tool_call_id", part.Get("tool_use_id").String())
-						toolResultJSON, _ = sjson.Set(toolResultJSON, "content", convertClaudeToolResultContentToString(part.Get("content")))
+						toolResultContent, toolResultContentRaw := convertClaudeToolResultContent(part.Get("content"))
+						if toolResultContentRaw {
+							toolResultJSON, _ = sjson.SetRaw(toolResultJSON, "content", toolResultContent)
+						} else {
+							toolResultJSON, _ = sjson.Set(toolResultJSON, "content", toolResultContent)
+						}
 						toolResults = append(toolResults, toolResultJSON)
 					}
 					return true
@@ -374,21 +379,41 @@ func convertClaudeContentPart(part gjson.Result) (string, bool) {
 	}
 }
 
-func convertClaudeToolResultContentToString(content gjson.Result) string {
+func convertClaudeToolResultContent(content gjson.Result) (string, bool) {
 	if !content.Exists() {
-		return ""
+		return "", false
 	}
 
 	if content.Type == gjson.String {
-		return content.String()
+		return content.String(), false
 	}
 
 	if content.IsArray() {
 		var parts []string
+		contentJSON := "[]"
+		hasImagePart := false
 		content.ForEach(func(_, item gjson.Result) bool {
 			switch {
 			case item.Type == gjson.String:
-				parts = append(parts, item.String())
+				text := item.String()
+				parts = append(parts, text)
+				textContent := `{"type":"text","text":""}`
+				textContent, _ = sjson.Set(textContent, "text", text)
+				contentJSON, _ = sjson.SetRaw(contentJSON, "-1", textContent)
+			case item.IsObject() && item.Get("type").String() == "text":
+				text := item.Get("text").String()
+				parts = append(parts, text)
+				textContent := `{"type":"text","text":""}`
+				textContent, _ = sjson.Set(textContent, "text", text)
+				contentJSON, _ = sjson.SetRaw(contentJSON, "-1", textContent)
+			case item.IsObject() && item.Get("type").String() == "image":
+				contentItem, ok := convertClaudeContentPart(item)
+				if ok {
+					contentJSON, _ = sjson.SetRaw(contentJSON, "-1", contentItem)
+					hasImagePart = true
+				} else {
+					parts = append(parts, item.Raw)
+				}
 			case item.IsObject() && item.Get("text").Exists() && item.Get("text").Type == gjson.String:
 				parts = append(parts, item.Get("text").String())
 			default:
@@ -397,19 +422,31 @@ func convertClaudeToolResultContentToString(content gjson.Result) string {
 			return true
 		})
 
+		if hasImagePart {
+			return contentJSON, true
+		}
+
 		joined := strings.Join(parts, "\n\n")
 		if strings.TrimSpace(joined) != "" {
-			return joined
+			return joined, false
 		}
-		return content.Raw
+		return content.Raw, false
 	}
 
 	if content.IsObject() {
-		if text := content.Get("text"); text.Exists() && text.Type == gjson.String {
-			return text.String()
+		if content.Get("type").String() == "image" {
+			contentItem, ok := convertClaudeContentPart(content)
+			if ok {
+				contentJSON := "[]"
+				contentJSON, _ = sjson.SetRaw(contentJSON, "-1", contentItem)
+				return contentJSON, true
+			}
 		}
-		return content.Raw
+		if text := content.Get("text"); text.Exists() && text.Type == gjson.String {
+			return text.String(), false
+		}
+		return content.Raw, false
 	}
 
-	return content.Raw
+	return content.Raw, false
 }

internal/translator/openai/claude/openai_claude_request_test.go

@@ -488,6 +488,114 @@ func TestConvertClaudeRequestToOpenAI_ToolResultObjectContent(t *testing.T) {
 	}
 }
 
+func TestConvertClaudeRequestToOpenAI_ToolResultTextAndImageContent(t *testing.T) {
+	inputJSON := `{
+		"model": "claude-3-opus",
+		"messages": [
+			{
+				"role": "assistant",
+				"content": [
+					{"type": "tool_use", "id": "call_1", "name": "do_work", "input": {"a": 1}}
+				]
+			},
+			{
+				"role": "user",
+				"content": [
+					{
+						"type": "tool_result",
+						"tool_use_id": "call_1",
+						"content": [
+							{"type": "text", "text": "tool ok"},
+							{
+								"type": "image",
+								"source": {
+									"type": "base64",
+									"media_type": "image/png",
+									"data": "iVBORw0KGgoAAAANSUhEUg=="
+								}
+							}
+						]
+					}
+				]
+			}
+		]
+	}`
+
+	result := ConvertClaudeRequestToOpenAI("test-model", []byte(inputJSON), false)
+	resultJSON := gjson.ParseBytes(result)
+	messages := resultJSON.Get("messages").Array()
+
+	if len(messages) != 2 {
+		t.Fatalf("Expected 2 messages, got %d. Messages: %s", len(messages), resultJSON.Get("messages").Raw)
+	}
+
+	toolContent := messages[1].Get("content")
+	if !toolContent.IsArray() {
+		t.Fatalf("Expected tool content array, got %s", toolContent.Raw)
+	}
+	if got := toolContent.Get("0.type").String(); got != "text" {
+		t.Fatalf("Expected first tool content type %q, got %q", "text", got)
+	}
+	if got := toolContent.Get("0.text").String(); got != "tool ok" {
+		t.Fatalf("Expected first tool content text %q, got %q", "tool ok", got)
+	}
+	if got := toolContent.Get("1.type").String(); got != "image_url" {
+		t.Fatalf("Expected second tool content type %q, got %q", "image_url", got)
+	}
+	if got := toolContent.Get("1.image_url.url").String(); got != "data:image/png;base64,iVBORw0KGgoAAAANSUhEUg==" {
+		t.Fatalf("Unexpected image_url: %q", got)
+	}
+}
+
+func TestConvertClaudeRequestToOpenAI_ToolResultURLImageOnly(t *testing.T) {
+	inputJSON := `{
+		"model": "claude-3-opus",
+		"messages": [
+			{
+				"role": "assistant",
+				"content": [
+					{"type": "tool_use", "id": "call_1", "name": "do_work", "input": {"a": 1}}
+				]
+			},
+			{
+				"role": "user",
+				"content": [
+					{
+						"type": "tool_result",
+						"tool_use_id": "call_1",
+						"content": {
+							"type": "image",
+							"source": {
+								"type": "url",
+								"url": "https://example.com/tool.png"
+							}
+						}
+					}
+				]
+			}
+		]
+	}`
+
+	result := ConvertClaudeRequestToOpenAI("test-model", []byte(inputJSON), false)
+	resultJSON := gjson.ParseBytes(result)
+	messages := resultJSON.Get("messages").Array()
+
+	if len(messages) != 2 {
+		t.Fatalf("Expected 2 messages, got %d. Messages: %s", len(messages), resultJSON.Get("messages").Raw)
+	}
+
+	toolContent := messages[1].Get("content")
+	if !toolContent.IsArray() {
+		t.Fatalf("Expected tool content array, got %s", toolContent.Raw)
+	}
+	if got := toolContent.Get("0.type").String(); got != "image_url" {
+		t.Fatalf("Expected tool content type %q, got %q", "image_url", got)
+	}
+	if got := toolContent.Get("0.image_url.url").String(); got != "https://example.com/tool.png" {
+		t.Fatalf("Unexpected image_url: %q", got)
+	}
+}
+
 func TestConvertClaudeRequestToOpenAI_AssistantTextToolUseTextOrder(t *testing.T) {
 	inputJSON := `{
 		"model": "claude-3-opus",