Enable .NET SDK code analyzers (#41)

.editorconfig

@@ -0,0 +1,18 @@
+# Remove the line below if you want to inherit .editorconfig settings from higher directories
+root = true
+
+# C# files
+[*.cs]
+
+# Code Analysis
+dotnet_diagnostic.CA1002.severity = none            # CA1002: Do not expose generic lists
+dotnet_diagnostic.CA1031.severity = none            # CA1031: Do not catch general exception types
+dotnet_diagnostic.CA1054.severity = none            # CA1054: URI-like parameters should not be strings
+dotnet_diagnostic.CA1056.severity = none            # CA1056: URI-like properties should not be strings
+dotnet_diagnostic.CA1062.severity = suggestion      # CA1062: Validate arguments of public methods
+dotnet_diagnostic.CA1510.severity = suggestion      # CA1510: Use ArgumentNullException throw helper
+dotnet_diagnostic.CA1849.severity = suggestion      # CA1849: Call async methods when in an async method
+dotnet_diagnostic.CA2000.severity = suggestion      # CA2000: Dispose objects before losing scope
+dotnet_diagnostic.CA2227.severity = suggestion      # CA2227: Collection properties should be read only
+dotnet_diagnostic.CA2249.severity = suggestion      # CA2249: Use 'string.Contains' instead of 'string.IndexOf'
+dotnet_diagnostic.CA1819.severity = suggestion      # CA1819: Properties should not return arrays

samples/TestServerWithHosting/Tools/EchoTool.cs

@@ -5,7 +5,7 @@ namespace TestServerWithHosting.Tools;
 [McpToolType]
 public static class EchoTool
 {
-    [McpTool(Description = "Echoes the input back to the client.")]
+    [McpTool(description: "Echoes the input back to the client.")]
     public static string Echo([McpParameter(true)] string message)
     {
         return "hello " + message;

samples/TestServerWithHosting/Tools/SampleLlmTool.cs

@@ -16,8 +16,11 @@ public class SampleLlmTool
         _server = server ?? throw new ArgumentNullException(nameof(server));
     }
 
-    [McpTool(Name = "sampleLLM", Description = "Samples from an LLM using MCP's sampling feature")]
-    public async Task<string> SampleLLM([McpParameter(true, Description = "The prompt to send to the LLM")] string prompt, [McpParameter(true, Description = "Maximum number of tokens to generate")] int maxTokens, CancellationToken cancellationToken)
+    [McpTool(name: "sampleLLM", description: "Samples from an LLM using MCP's sampling feature")]
+    public async Task<string> SampleLLM(
+        [McpParameter(true, description: "The prompt to send to the LLM")] string prompt,
+        [McpParameter(true, description: "Maximum number of tokens to generate")] int maxTokens,
+        CancellationToken cancellationToken)
     {
         var samplingParams = CreateRequestSamplingParams(prompt ?? string.Empty, "sampleLLM", maxTokens);
         var sampleResult = await _server.RequestSamplingAsync(samplingParams, cancellationToken);

samples/anthropic/tools/ToolsConsole/McpToolExtensions.cs

@@ -2,10 +2,17 @@
 using System.Text.Json;
 using System.Text.Json.Nodes;
 
+namespace McpDotNet;
+
 public static class McpToolExtensions
 {
     public static IList<Anthropic.SDK.Common.Tool> ToAnthropicTools(this IEnumerable<McpDotNet.Protocol.Types.Tool> tools)
     {
+        if (tools is null)
+        {
+            throw new ArgumentNullException(nameof(tools));
+        }
+
         List<Anthropic.SDK.Common.Tool> result = [];
         foreach (var tool in tools)
         {

samples/anthropic/tools/ToolsConsole/Program.cs

@@ -1,6 +1,7 @@
 using Anthropic.SDK;
 using Anthropic.SDK.Constants;
 using Anthropic.SDK.Messaging;
+using McpDotNet;
 using McpDotNet.Client;
 using McpDotNet.Configuration;
 using McpDotNet.Protocol.Transport;

samples/microsoft.extensions.ai/tools/ToolsConsole/McpAIFunction.cs

@@ -29,6 +29,11 @@ public class McpAIFunction : AIFunction
 
     protected async override Task<object?> InvokeCoreAsync(IEnumerable<KeyValuePair<string, object?>> arguments, CancellationToken cancellationToken)
     {
+        if (arguments is null)
+        {
+            throw new ArgumentNullException(nameof(arguments));
+        }
+
         // Convert arguments to dictionary format expected by mcpdotnet
         Dictionary<string, object> argDict = [];
         foreach (var arg in arguments)

src/McpDotNet.Extensions.AI/McpAIFunction.cs

@@ -34,6 +34,11 @@ public class McpAIFunction : AIFunction
     /// <inheritdoc/>
     protected async override Task<object?> InvokeCoreAsync(IEnumerable<KeyValuePair<string, object?>> arguments, CancellationToken cancellationToken)
     {
+        if (arguments is null)
+        {
+            throw new ArgumentNullException(nameof(arguments));
+        }
+
         // Convert arguments to dictionary format expected by mcpdotnet
         Dictionary<string, object> argDict = [];
         foreach (var arg in arguments)
@@ -45,7 +50,7 @@ public class McpAIFunction : AIFunction
         }
 
         // Call the tool through mcpdotnet
-        var result = await _client.CallToolAsync(_tool.Name, argDict, cancellationToken);
+        var result = await _client.CallToolAsync(_tool.Name, argDict, cancellationToken).ConfigureAwait(false);
 
         // Extract the text content from the result.
         return string.Join("\n", result.Content

src/McpDotNet.Extensions.AI/McpDotNet.Extensions.AI.csproj

@@ -5,6 +5,8 @@
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <LangVersion>Latest</LangVersion>
+    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <AnalysisMode>All</AnalysisMode>
   </PropertyGroup>
 
   <PropertyGroup>

src/McpDotNet.Extensions.AI/McpSessionScope.cs

@@ -12,7 +12,7 @@ namespace McpDotNet.Extensions.AI;
 /// 
 /// Disposing the scope will dispose all clients and tools, and close all connections.
 /// </summary>
-public class McpSessionScope : IAsyncDisposable
+public sealed class McpSessionScope : IAsyncDisposable
 {
     private readonly List<IMcpClient> _clients = [];
     private bool _disposed;
@@ -39,9 +39,14 @@ public class McpSessionScope : IAsyncDisposable
         McpClientOptions? options = null,
         ILoggerFactory? loggerFactory = null)
     {
+        if (serverConfig is null)
+        {
+            throw new ArgumentNullException(nameof(serverConfig));
+        }
+
         var scope = new McpSessionScope();
-        var client = await scope.AddClientAsync(serverConfig, options, loggerFactory);
-        var tools = await client.ListToolsAsync();
+        var client = await scope.AddClientAsync(serverConfig, options, loggerFactory).ConfigureAwait(false);
+        var tools = await client.ListToolsAsync().ConfigureAwait(false);
         scope.Tools = tools.Tools.Select(t => new McpAIFunction(t, client)).ToList<AITool>();
         if (!string.IsNullOrEmpty(client.ServerInstructions))
         {
@@ -61,11 +66,16 @@ public class McpSessionScope : IAsyncDisposable
         McpClientOptions? options = null,
         ILoggerFactory? loggerFactory = null)
     {
+        if (serverConfigs is null)
+        {
+            throw new ArgumentNullException(nameof(serverConfigs));
+        }
+
         var scope = new McpSessionScope();
         foreach (var config in serverConfigs)
         {
-            var client = await scope.AddClientAsync(config, options, loggerFactory);
-            var tools = await client.ListToolsAsync();
+            var client = await scope.AddClientAsync(config, options, loggerFactory).ConfigureAwait(false);
+            var tools = await client.ListToolsAsync().ConfigureAwait(false);
             scope.Tools = scope.Tools.Concat(tools.Tools.Select(t => new McpAIFunction(t, client))).ToList();
         }
         scope.ServerInstructions = scope._clients.Select(c => c.ServerInstructions).Where(s => !string.IsNullOrEmpty(s)).ToList()!;
@@ -79,7 +89,7 @@ public class McpSessionScope : IAsyncDisposable
         var factory = new McpClientFactory([config],
             options ?? new() { ClientInfo = new() { Name = "AnonymousClient", Version = "1.0.0.0" } },
             loggerFactory ?? NullLoggerFactory.Instance);
-        var client = await factory.GetClientAsync(config.Id);
+        var client = await factory.GetClientAsync(config.Id).ConfigureAwait(false);
         _clients.Add(client);
         return client;
     }
@@ -92,7 +102,7 @@ public class McpSessionScope : IAsyncDisposable
 
         foreach (var client in _clients)
         {
-            await client.DisposeAsync();
+            await client.DisposeAsync().ConfigureAwait(false);
         }
         _clients.Clear();
         Tools = [];

src/mcpdotnet/Client/IMcpClient.cs

@@ -1,8 +1,8 @@
-namespace McpDotNet.Client;
-
-using McpDotNet.Protocol.Messages;
+using McpDotNet.Protocol.Messages;
 using McpDotNet.Protocol.Types;
 
+namespace McpDotNet.Client;
+
 /// <summary>
 /// Represents an instance of the MCP client connecting to a specific server.
 /// Use PingAsync, ListToolsAsync and CallToolAsync instead of SendRequestAsync for common operations.

src/mcpdotnet/Client/McpClient.cs

@@ -55,7 +55,7 @@ internal class McpClient : McpJsonRpcEndpoint, IMcpClient
                         throw new McpClientException("Sampling handler not configured");
                     }
 
-                    return await SamplingHandler(request, CancellationTokenSource?.Token ?? CancellationToken.None);
+                    return await SamplingHandler(request, CancellationTokenSource?.Token ?? CancellationToken.None).ConfigureAwait(false);
                 });
         }
         if (options.Capabilities?.Roots != null)
@@ -69,7 +69,7 @@ internal class McpClient : McpJsonRpcEndpoint, IMcpClient
                         _logger.RootsHandlerNotConfigured(EndpointName);
                         throw new McpClientException("Roots handler not configured");
                     }
-                    return await RootsHandler(request, CancellationTokenSource?.Token ?? CancellationToken.None);
+                    return await RootsHandler(request, CancellationTokenSource?.Token ?? CancellationToken.None).ConfigureAwait(false);
                 });
         }
     }

src/mcpdotnet/Client/McpClientException.cs

@@ -10,6 +10,13 @@ public class McpClientException : Exception
     /// </summary>
     public int? ErrorCode { get; }
 
+    /// <summary>
+    /// Initializes a new instance of the <see cref="McpClientException"/> class.
+    /// </summary>
+    public McpClientException()
+    {
+    }
+
     /// <summary>
     /// Initializes a new instance of the <see cref="McpClientException"/> class with a specified error message.
     /// </summary>

src/mcpdotnet/Client/McpClientFactory.cs

@@ -81,7 +81,7 @@ public class McpClientFactory
 
         var transport = _transportFactoryMethod(config);
         var client = _clientFactoryMethod(transport, config, _clientOptions);
-        await client.ConnectAsync(cancellationToken);
+        await client.ConnectAsync(cancellationToken).ConfigureAwait(false);
 
         _logger.ClientCreated(endpointName);
 
@@ -97,29 +97,36 @@ public class McpClientFactory
 
         var options = string.Join(", ", config.TransportOptions?.Select(kv => $"{kv.Key}={kv.Value}") ?? []);
         _logger.CreatingTransport(endpointName, config.TransportType, options);
-        return config.TransportType.ToLowerInvariant() switch
+
+        if (string.Equals(config.TransportType, TransportTypes.StdIo, StringComparison.OrdinalIgnoreCase))
         {
-            TransportTypes.StdIo => new StdioClientTransport(new StdioClientTransportOptions
+            return new StdioClientTransport(new StdioClientTransportOptions
             {
                 Command = GetCommand(config),
                 Arguments = config.TransportOptions?.GetValueOrDefault("arguments")?.Split(' '),
                 WorkingDirectory = config.TransportOptions?.GetValueOrDefault("workingDirectory"),
                 EnvironmentVariables = config.TransportOptions?
-                    .Where(kv => kv.Key.StartsWith("env:"))
+                    .Where(kv => kv.Key.StartsWith("env:", StringComparison.Ordinal))
                     .ToDictionary(kv => kv.Key.Substring(4), kv => kv.Value)
-            }, config, _loggerFactory),
-            TransportTypes.Sse or "http" => new SseClientTransport(
+            }, config, _loggerFactory);
+        }
+
+        if (string.Equals(config.TransportType, TransportTypes.Sse, StringComparison.OrdinalIgnoreCase) ||
+            string.Equals(config.TransportType, "http", StringComparison.OrdinalIgnoreCase))
+        {
+            return new SseClientTransport(
                new SseClientTransportOptions
                {
                    ConnectionTimeout = TimeSpan.FromSeconds(ParseOrDefault(config.TransportOptions, "connectionTimeout", 30)),
                    MaxReconnectAttempts = ParseOrDefault(config.TransportOptions, "maxReconnectAttempts", 3),
                    ReconnectDelay = TimeSpan.FromSeconds(ParseOrDefault(config.TransportOptions, "reconnectDelay", 5)),
                    AdditionalHeaders = config.TransportOptions?
-                       .Where(kv => kv.Key.StartsWith("header."))
+                       .Where(kv => kv.Key.StartsWith("header.", StringComparison.Ordinal))
                        .ToDictionary(kv => kv.Key.Substring(7), kv => kv.Value)
-               }, config, _loggerFactory),
-            _ => throw new ArgumentException($"Unsupported transport type '{config.TransportType}'.", nameof(config))
-        };
+               }, config, _loggerFactory);
+        }
+
+        throw new ArgumentException($"Unsupported transport type '{config.TransportType}'.", nameof(config));
     }
 
     private static int ParseOrDefault(Dictionary<string, string>? options, string key, int defaultValue)

src/mcpdotnet/Configuration/McpServerBuilderExtensions.Handler.cs

@@ -17,6 +17,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithListToolsHandler(this IMcpServerBuilder builder, Func<RequestContext<ListToolsRequestParams>, CancellationToken, Task<ListToolsResult>> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.ListToolsHandler = handler);
         return builder;
     }
@@ -28,6 +33,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithCallToolHandler(this IMcpServerBuilder builder, Func<RequestContext<CallToolRequestParams>, CancellationToken, Task<CallToolResponse>> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.CallToolHandler = handler);
         return builder;
     }
@@ -39,6 +49,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithListPromptsHandler(this IMcpServerBuilder builder, Func<RequestContext<ListPromptsRequestParams>, CancellationToken, Task<ListPromptsResult>> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.ListPromptsHandler = handler);
         return builder;
     }
@@ -50,6 +65,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithGetPromptHandler(this IMcpServerBuilder builder, Func<RequestContext<GetPromptRequestParams>, CancellationToken, Task<GetPromptResult>> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.GetPromptHandler = handler);
         return builder;
     }
@@ -61,6 +81,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithListResourcesHandler(this IMcpServerBuilder builder, Func<RequestContext<ListResourcesRequestParams>, CancellationToken, Task<ListResourcesResult>> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.ListResourcesHandler = handler);
         return builder;
     }
@@ -72,6 +97,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithReadResourceHandler(this IMcpServerBuilder builder, Func<RequestContext<ReadResourceRequestParams>, CancellationToken, Task<ReadResourceResult>> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.ReadResourceHandler = handler);
         return builder;
     }
@@ -83,6 +113,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithGetCompletionHandler(this IMcpServerBuilder builder, Func<RequestContext<CompleteRequestParams>, CancellationToken, Task<CompleteResult>> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.GetCompletionHandler = handler);
         return builder;
     }
@@ -94,6 +129,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithSubscribeToResourcesHandler(this IMcpServerBuilder builder, Func<RequestContext<string>, CancellationToken, Task> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.SubscribeToResourcesHandler = handler);
         return builder;
     }
@@ -105,6 +145,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="handler">The handler.</param>
     public static IMcpServerBuilder WithUnsubscribeFromResourcesHandler(this IMcpServerBuilder builder, Func<RequestContext<string>, CancellationToken, Task> handler)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.Configure<McpServerDelegates>(s => s.UnsubscribeFromResourcesHandler = handler);
         return builder;
     }

src/mcpdotnet/Configuration/McpServerBuilderExtensions.Tools.cs

@@ -1,4 +1,5 @@
-using System.Reflection;
+using System.Globalization;
+using System.Reflection;
 using System.Text.Json;
 using McpDotNet.Configuration;
 using McpDotNet.Protocol.Types;
@@ -37,6 +38,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="toolTypes">Types with marked methods to add as tools to the server.</param>
     public static IMcpServerBuilder WithTools(this IMcpServerBuilder builder, params Type[] toolTypes)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         if (toolTypes is null || toolTypes.Length == 0)
             throw new ArgumentException("At least one tool type must be provided.", nameof(toolTypes));
 
@@ -54,7 +60,7 @@ public static partial class McpServerBuilderExtensions
                     var tool = CreateTool(method, attribute);
                     tools.Add(tool);
 
-                    callbacks.Add(tool.Name, async (request, cancellationToken) => await CallTool(request, method, cancellationToken));
+                    callbacks.Add(tool.Name, async (request, cancellationToken) => await CallTool(request, method, cancellationToken).ConfigureAwait(false));
 
                     // register type because method is not static and so we need an instance
                     if (!method.IsStatic)
@@ -68,7 +74,7 @@ public static partial class McpServerBuilderExtensions
         builder.WithCallToolHandler(async (request, cancellationToken) =>
         {
             if (request.Params != null && callbacks.TryGetValue(request.Params.Name, out var callback))
-                return await callback(request, cancellationToken);
+                return await callback(request, cancellationToken).ConfigureAwait(false);
 
             throw new McpServerException($"Unknown tool: {request.Params?.Name}");
         });
@@ -219,7 +225,7 @@ public static partial class McpServerBuilderExtensions
                 if (value is JsonElement element)
                     value = JsonSerializer.Deserialize(element.GetRawText(), parameter.ParameterType);
 
-                parameters.Add(Convert.ChangeType(value, parameter.ParameterType));
+                parameters.Add(Convert.ChangeType(value, parameter.ParameterType, CultureInfo.InvariantCulture));
             }
             else
             {

src/mcpdotnet/Configuration/McpServerBuilderExtensions.Transports.cs

@@ -15,6 +15,11 @@ public static partial class McpServerBuilderExtensions
     /// <param name="builder">The builder instance.</param>
     public static IMcpServerBuilder WithStdioServerTransport(this IMcpServerBuilder builder)
     {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
         builder.Services.AddSingleton<IServerTransport, StdioServerTransport>();
         return builder;
     }

src/mcpdotnet/Hosting/McpServerHostedService.cs

@@ -23,6 +23,6 @@ public class McpServerHostedService : BackgroundService
     /// <inheritdoc />
     protected override async Task ExecuteAsync(CancellationToken stoppingToken)
     {
-        await _server.StartAsync(stoppingToken);
+        await _server.StartAsync(stoppingToken).ConfigureAwait(false);
     }
 }

src/mcpdotnet/Protocol/Messages/JsonRpcError.cs

@@ -1,6 +1,6 @@
-namespace McpDotNet.Protocol.Messages;
+using System.Text.Json.Serialization;
 
-using System.Text.Json.Serialization;
+namespace McpDotNet.Protocol.Messages;
 
 /// <summary>
 /// An error response message in the JSON-RPC protocol.

src/mcpdotnet/Protocol/Messages/JsonRpcErrorDetail.cs

@@ -1,6 +1,6 @@
-namespace McpDotNet.Protocol.Messages;
+using System.Text.Json.Serialization;
 
-using System.Text.Json.Serialization;
+namespace McpDotNet.Protocol.Messages;
 
 /// <summary>
 /// Detailed error information for JSON-RPC error responses.

src/mcpdotnet/Protocol/Messages/JsonRpcMessage.cs

@@ -1,6 +1,6 @@
-namespace McpDotNet.Protocol.Messages;
+using System.Text.Json.Serialization;
 
-using System.Text.Json.Serialization;
+namespace McpDotNet.Protocol.Messages;
 
 /// <summary>
 /// A request message in the JSON-RPC protocol.