Add agentic code execution tool support

See https://docs.x.ai/docs/guides/tools/code-execution-tool.

Author: kzu

src/Extensions.Grok/GrokChatClient.cs

@@ -1,10 +1,8 @@
 using System.Text.Json;
-
-using Microsoft.Extensions.AI;
-
+using Devlooped.Grok;
 using Grpc.Core;
 using Grpc.Net.Client;
-using Devlooped.Grok;
+using Microsoft.Extensions.AI;
 using static Devlooped.Grok.Chat;
 
 namespace Devlooped.Extensions.AI.Grok;
@@ -25,7 +23,7 @@ internal GrokChatClient(GrpcChannel channel, GrokClientOptions clientOptions, st
     public async Task<ChatResponse> GetResponseAsync(IEnumerable<ChatMessage> messages, ChatOptions? options = null, CancellationToken cancellationToken = default)
     {
         var requestDto = MapToRequest(messages, options);
-        
+
         var protoResponse = await client.GetCompletionAsync(requestDto, cancellationToken: cancellationToken);
 
         var chatMessages = protoResponse.Outputs
@@ -34,7 +32,7 @@ public async Task<ChatResponse> GetResponseAsync(IEnumerable<ChatMessage> messag
             .ToList();
 
         var lastOutput = protoResponse.Outputs.LastOrDefault();
-        
+
         return new ChatResponse(chatMessages)
         {
             ResponseId = protoResponse.Id,
@@ -52,13 +50,13 @@ public IAsyncEnumerable<ChatResponseUpdate> GetStreamingResponseAsync(IEnumerabl
         async IAsyncEnumerable<ChatResponseUpdate> CompleteChatStreamingCore(IEnumerable<ChatMessage> messages, ChatOptions? options, [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken)
         {
             var requestDto = MapToRequest(messages, options);
-            
+
             using var call = client.GetCompletionChunk(requestDto, cancellationToken: cancellationToken);
-            
+
             await foreach (var chunk in call.ResponseStream.ReadAllAsync(cancellationToken))
             {
                 var outputChunk = chunk.Outputs[0];
-                
+
                 // Use positional arguments for ChatResponseUpdate
                 var update = new ChatResponseUpdate(
                     outputChunk.Delta.Role != MessageRole.InvalidRole ? MapRole(outputChunk.Delta.Role) : null,
@@ -79,7 +77,7 @@ async IAsyncEnumerable<ChatResponseUpdate> CompleteChatStreamingCore(IEnumerable
                         textContent = new TextContent(string.Empty);
                         update.Contents.Add(textContent);
                     }
-                    
+
                     foreach (var citation in citations.Distinct())
                     {
                         (textContent.Annotations ??= []).Add(new CitationAnnotation { Url = new(citation) });
@@ -150,7 +148,7 @@ GetCompletionsRequest MapToRequest(IEnumerable<ChatMessage> messages, ChatOption
         foreach (var message in messages)
         {
             var gmsg = new Message { Role = MapRole(message.Role) };
-            
+
             foreach (var content in message.Contents)
             {
                 if (content is TextContent textContent && !string.IsNullOrEmpty(textContent.Text))
@@ -250,6 +248,10 @@ GetCompletionsRequest MapToRequest(IEnumerable<ChatMessage> messages, ChatOption
                         request.Tools.Add(new Tool { WebSearch = new WebSearch() });
                     }
                 }
+                else if (tool is HostedCodeInterpreterTool)
+                {
+                    request.Tools.Add(new Tool { CodeExecution = new CodeExecution { } });
+                }
             }
         }
 
@@ -272,7 +274,7 @@ GetCompletionsRequest MapToRequest(IEnumerable<ChatMessage> messages, ChatOption
         _ when role == ChatRole.Tool => MessageRole.RoleTool,
         _ => MessageRole.RoleUser
     };
-    
+
     static ChatRole MapRole(MessageRole role) => role switch
     {
         MessageRole.RoleSystem => ChatRole.System,
@@ -299,8 +301,8 @@ GetCompletionsRequest MapToRequest(IEnumerable<ChatMessage> messages, ChatOption
         TotalTokenCount = usage.TotalTokens
     };
 
-    public object? GetService(Type serviceType, object? serviceKey = null) => 
+    public object? GetService(Type serviceType, object? serviceKey = null) =>
         serviceType == typeof(GrokChatClient) ? this : null;
 
-    public void Dispose() {}
+    public void Dispose() { }
 }

src/Extensions.Grok/GrokClient.cs

@@ -26,8 +26,8 @@ public class GrokClient(string apiKey, GrokClientOptions options)
     internal GrpcChannel Channel => channels.GetOrAdd((Endpoint, ApiKey), key =>
     {
         var handler = new AuthenticationHeaderHandler(ApiKey)
-        { 
-            InnerHandler = Options.ChannelOptions?.HttpHandler ?? new HttpClientHandler() 
+        {
+            InnerHandler = Options.ChannelOptions?.HttpHandler ?? new HttpClientHandler()
         };
 
         var options = Options.ChannelOptions ?? new GrpcChannelOptions();

src/Tests/GrokTests.cs

@@ -65,13 +65,13 @@ public async Task GrokInvokesToolAndSearch()
         {
             ModelId = "grok-4-1-fast-non-reasoning",
             Search = GrokSearch.Web,
-            Tools = [AIFunctionFactory.Create(() => 
+            Tools = [AIFunctionFactory.Create(() =>
             {
                 getDateCalls++;
                 return DateTimeOffset.Now.ToString("O");
             }, "get_date", "Gets the current date")],
         };
-        
+
         var response = await grok.GetResponseAsync(messages, options);
 
         // The get_date result shows up as a tool role
@@ -178,14 +178,14 @@ public async Task GrokInvokesGrokSearchToolIncludesDomain()
 
         var options = new ChatOptions
         {
-            Tools = [new GrokSearchTool 
-            { 
+            Tools = [new GrokSearchTool
+            {
                 AllowedDomains = ["microsoft.com", "news.microsoft.com"],
             }]
         };
 
         var response = await grok.GetResponseAsync(messages, options);
-        
+
         Assert.NotNull(response.Text);
         Assert.Contains("Microsoft", response.Text);
 
@@ -242,4 +242,28 @@ public async Task GrokInvokesGrokSearchToolExcludesDomain()
 
         Assert.DoesNotContain(urls, x => x.Host == "blogs.microsoft.com");
     }
+
+    [SecretsFact("XAI_API_KEY")]
+    public async Task GrokInvokesHostedCodeExecution()
+    {
+        var messages = new Chat()
+        {
+            { "user", "Calculate the compound interest for $10,000 at 5% annually for 10 years" },
+        };
+
+        var grok = new GrokClient(Configuration["XAI_API_KEY"]!).AsIChatClient("grok-4-fast");
+
+        var options = new ChatOptions
+        {
+            Tools = [new HostedCodeInterpreterTool()]
+        };
+
+        var response = await grok.GetResponseAsync(messages, options);
+        var text = response.Text;
+
+        Assert.Contains("$6,288.95", text);
+        Assert.Contains(
+            response.Messages.SelectMany(x => x.Contents).OfType<HostedToolCallContent>(),
+            x => x.ToolCall.Type == Devlooped.Grok.ToolCallType.CodeExecutionTool);
+    }
 }