Address review comments for timeout bounds and test refactoring

Co-authored-by: JerryNixon <1749983+JerryNixon@users.noreply.github.com>

Author: Copilot

src/Azure.DataApiBuilder.Mcp/BuiltInTools/AggregateRecordsTool.cs

@@ -36,6 +36,7 @@ public class AggregateRecordsTool : IMcpTool
         public ToolType ToolType { get; } = ToolType.BuiltIn;
 
         private static readonly HashSet<string> _validFunctions = new(StringComparer.OrdinalIgnoreCase) { "count", "avg", "sum", "min", "max" };
+        // Supported HAVING operators for post-aggregation filtering.
         private static readonly HashSet<string> _validHavingOperators = new(StringComparer.OrdinalIgnoreCase) { "eq", "neq", "gt", "gte", "lt", "lte", "in" };
 
         public Tool GetToolMetadata()
@@ -253,7 +254,7 @@ public async Task<CallToolResult> ExecuteAsync(
                             return McpResponseBuilder.BuildErrorResult(
                                 toolName,
                                 "InvalidArguments",
-                                $"Unsupported having operator '{prop.Name}'. Supported operators are: eq, neq, gt, gte, lt, lte, in.",
+                                $"Unsupported having operator '{prop.Name}'. Supported operators are: {string.Join(", ", _validHavingOperators)}.",
                                 logger);
                         }
 

src/Service.Tests/Mcp/AggregateRecordsToolTests.cs

@@ -111,10 +111,10 @@ public async Task AggregateRecords_DisabledConfigurations_ReturnToolDisabledErro
         [DataRow("{\"entity\": \"Book\", \"function\": \"count\", \"field\": \"*\", \"having\": { \"between\": 10 }}", "Unsupported having operator", DisplayName = "Unsupported having operator returns InvalidArguments")]
         [DataRow("{\"entity\": \"Book\", \"function\": \"count\", \"field\": \"*\", \"having\": { \"eq\": \"10\" }}", "must be a numeric value", DisplayName = "Non-numeric having value returns InvalidArguments")]
         [DataRow("{\"entity\": \"Book\", \"function\": \"count\", \"field\": \"*\", \"having\": { \"in\": [1, \"x\"] }}", "must contain only numeric values", DisplayName = "Non-numeric having.in value returns InvalidArguments")]
-        public async Task AggregateRecords_InvalidArguments_ReturnInvalidArguments(string? argsJson, string? expectedMessageFragment)
+        public async Task AggregateRecords_InvalidArguments_ReturnInvalidArguments(string? argumentsJson, string? expectedMessageFragment)
         {
             RuntimeConfig config = CreateConfig();
-            CallToolResult result = await ExecuteWithConfigAsync(config, argsJson);
+            CallToolResult result = await ExecuteWithConfigAsync(config, argumentsJson);
 
             Assert.IsTrue(result.IsError == true);
             JsonElement content = ParseContent(result);
@@ -1132,12 +1132,12 @@ private static JsonElement ParseContent(CallToolResult result)
             return JsonDocument.Parse(firstContent.Text).RootElement;
         }
 
-        private static async Task<CallToolResult> ExecuteWithConfigAsync(RuntimeConfig config, string? argsJson, CancellationToken cancellationToken = default)
+        private static async Task<CallToolResult> ExecuteWithConfigAsync(RuntimeConfig config, string? argumentsJson, CancellationToken cancellationToken = default)
         {
             IServiceProvider serviceProvider = CreateServiceProvider(config);
             AggregateRecordsTool tool = new();
-            JsonDocument? args = argsJson is null ? null : JsonDocument.Parse(argsJson);
-            return await tool.ExecuteAsync(args, serviceProvider, cancellationToken);
+            JsonDocument? arguments = argumentsJson is not null ? JsonDocument.Parse(argumentsJson) : null;
+            return await tool.ExecuteAsync(arguments, serviceProvider, cancellationToken);
         }
 
         private static void AssertToolDisabledError(JsonElement content)