test(antigravity): cover mixed web search transforms

backend/internal/pkg/antigravity/request_transformer_test.go

@@ -423,3 +423,36 @@ func TestTransformClaudeToGeminiWithOptions_PreservesBillingHeaderSystemBlock(t
 		})
 	}
 }
+
+func TestTransformClaudeToGeminiWithOptions_PreservesWebSearchAlongsideFunctions(t *testing.T) {
+	claudeReq := &ClaudeRequest{
+		Model: "claude-3-5-sonnet-latest",
+		Messages: []ClaudeMessage{
+			{
+				Role:    "user",
+				Content: json.RawMessage(`[{"type":"text","text":"hello"}]`),
+			},
+		},
+		Tools: []ClaudeTool{
+			{
+				Name:        "get_weather",
+				Description: "Get weather information",
+				InputSchema: map[string]any{"type": "object"},
+			},
+			{
+				Type: "web_search_20250305",
+				Name: "web_search",
+			},
+		},
+	}
+
+	body, err := TransformClaudeToGeminiWithOptions(claudeReq, "project-1", "gemini-2.5-flash", DefaultTransformOptions())
+	require.NoError(t, err)
+
+	var req V1InternalRequest
+	require.NoError(t, json.Unmarshal(body, &req))
+	require.Len(t, req.Request.Tools, 2)
+	require.Len(t, req.Request.Tools[0].FunctionDeclarations, 1)
+	require.Equal(t, "get_weather", req.Request.Tools[0].FunctionDeclarations[0].Name)
+	require.NotNil(t, req.Request.Tools[1].GoogleSearch)
+}