Add initial implementation of McpTool to Responses

.github/workflows/live-test.yml

@@ -32,7 +32,7 @@ jobs:
       - name: Run live tests
         run: dotnet test ./tests/OpenAI.Tests.csproj
           --configuration Release
-          --filter="TestCategory!=Smoke&TestCategory!=Assistants&TestCategory!=StoredChat&TestCategory!=Images&TestCategory!=Uploads&TestCategory!=Moderations&TestCategory!=FineTuning&TestCategory!=Conversation&TestCategory!=Manual"
+          --filter="TestCategory!=Smoke&TestCategory!=Assistants&TestCategory!=StoredChat&TestCategory!=Images&TestCategory!=Uploads&TestCategory!=Moderations&TestCategory!=FineTuning&TestCategory!=Conversation&TestCategory!=MCP&TestCategory!=Manual"
           --logger "trx;LogFilePrefix=live"
           --results-directory ${{github.workspace}}/artifacts/test-results
           ${{ env.version_suffix_args}}

.github/workflows/release.yml

@@ -55,7 +55,7 @@ jobs:
       - name: Run Live Tests
         run: dotnet test ./tests/OpenAI.Tests.csproj
           --configuration Release
-          --filter="TestCategory!=Smoke&TestCategory!=Assistants&TestCategory!=StoredChat&TestCategory!=Images&TestCategory!=Uploads&TestCategory!=Moderations&TestCategory!=FineTuning&TestCategory!=Conversation&TestCategory!=Manual"
+          --filter="TestCategory!=Smoke&TestCategory!=Assistants&TestCategory!=StoredChat&TestCategory!=Images&TestCategory!=Uploads&TestCategory!=Moderations&TestCategory!=FineTuning&TestCategory!=Conversation&TestCategory!=MCP&TestCategory!=Manual"
           --logger "trx;LogFilePrefix=live"
           --results-directory ${{ github.workspace }}/artifacts/test-results
           ${{ env.version_suffix_args }}

examples/Responses/Example01_SimpleResponse.cs

@@ -13,7 +13,7 @@ public partial class ResponseExamples
     [Test]
     public void Example01_SimpleResponse()
     {
-        OpenAIResponseClient client = new(model: "gpt-4o", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
+        OpenAIResponseClient client = new(model: "gpt-5", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
 
         OpenAIResponse response = client.CreateResponse("Say 'this is a test.'");
 

examples/Responses/Example01_SimpleResponseAsync.cs

@@ -14,7 +14,7 @@ public partial class ResponseExamples
     [Test]
     public async Task Example01_SimpleResponseAsync()
     {
-        OpenAIResponseClient client = new(model: "gpt-4o", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
+        OpenAIResponseClient client = new(model: "gpt-5", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
 
         OpenAIResponse response = await client.CreateResponseAsync("Say 'this is a test.'");
 

examples/Responses/Example02_SimpleResponseStreaming.cs

@@ -14,7 +14,7 @@ public partial class ResponseExamples
     [Test]
     public void Example02_SimpleResponseStreaming()
     {
-        OpenAIResponseClient client = new(model: "gpt-4o-mini", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
+        OpenAIResponseClient client = new(model: "gpt-5", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
 
         CollectionResult<StreamingResponseUpdate> responseUpdates = client.CreateResponseStreaming("Say 'this is a test.'");
 

examples/Responses/Example02_SimpleResponseStreamingAsync.cs

@@ -16,7 +16,7 @@ public partial class ResponseExamples
     [Test]
     public async Task Example02_SimpleResponseStreamingAsync()
     {
-        OpenAIResponseClient client = new(model: "gpt-4o-mini", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
+        OpenAIResponseClient client = new(model: "gpt-5", apiKey: Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
 
         AsyncCollectionResult<StreamingResponseUpdate> responseUpdates = client.CreateResponseStreamingAsync("Say 'this is a test.'");
 

examples/Responses/Example03_FunctionCalling.cs

@@ -0,0 +1,165 @@
+using NUnit.Framework;
+using OpenAI.Responses;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.Json;
+
+namespace OpenAI.Examples;
+
+// This example uses experimental APIs which are subject to change. To use experimental APIs,
+// please acknowledge their experimental status by suppressing the corresponding warning.
+#pragma warning disable OPENAI001
+
+public partial class ResponseExamples
+{
+    #region
+    private static string GetCurrentLocation()
+    {
+        // Call the location API here.
+        return "San Francisco";
+    }
+
+    private static string GetCurrentWeather(string location, string unit = "celsius")
+    {
+        // Call the weather API here.
+        return $"31 {unit}";
+    }
+    #endregion
+
+    #region
+    private static readonly FunctionTool getCurrentLocationTool = ResponseTool.CreateFunctionTool(
+        functionName: nameof(GetCurrentLocation),
+        functionDescription: "Get the user's current location",
+        functionParameters: null,
+        strictModeEnabled: false
+    );
+
+    private static readonly FunctionTool getCurrentWeatherTool = ResponseTool.CreateFunctionTool(
+        functionName: nameof(GetCurrentWeather),
+        functionDescription: "Get the current weather in a given location",
+        functionParameters: BinaryData.FromBytes("""
+            {
+                "type": "object",
+                "properties": {
+                    "location": {
+                        "type": "string",
+                        "description": "The city and state, e.g. Boston, MA"
+                    },
+                    "unit": {
+                        "type": "string",
+                        "enum": [ "celsius", "fahrenheit" ],
+                        "description": "The temperature unit to use. Infer this from the specified location."
+                    }
+                },
+                "required": [ "location" ]
+            }
+            """u8.ToArray()),
+        strictModeEnabled: false
+    );
+    #endregion
+
+    [Test]
+    public void Example03_FunctionCalling()
+    {
+        OpenAIResponseClient client = new("gpt-5", Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
+
+        List<ResponseItem> inputItems =
+        [
+            ResponseItem.CreateUserMessageItem("What's the weather like today for my current location?"),
+        ];
+
+        ResponseCreationOptions options = new()
+        {
+            Tools = { getCurrentLocationTool, getCurrentWeatherTool },
+        };
+
+        PrintMessageItems(inputItems.OfType<MessageResponseItem>());
+
+        bool requiresAction;
+
+        do
+        {
+            requiresAction = false;
+            OpenAIResponse response = client.CreateResponse(inputItems, options);
+
+            inputItems.AddRange(response.OutputItems);
+
+            foreach (ResponseItem outputItem in response.OutputItems)
+            {
+                if (outputItem is FunctionCallResponseItem functionCall)
+                {
+                    switch (functionCall.FunctionName)
+                    {
+                        case nameof(GetCurrentLocation):
+                            {
+                                string functionOutput = GetCurrentLocation();
+                                inputItems.Add(new FunctionCallOutputResponseItem(functionCall.CallId, functionOutput));
+                                break;
+                            }
+
+                        case nameof(GetCurrentWeather):
+                            {
+                                // The arguments that the model wants to use to call the function are specified as a
+                                // stringified JSON object based on the schema defined in the tool definition. Note that
+                                // the model may hallucinate arguments too. Consequently, it is important to do the
+                                // appropriate parsing and validation before calling the function.
+                                using JsonDocument argumentsJson = JsonDocument.Parse(functionCall.FunctionArguments);
+                                bool hasLocation = argumentsJson.RootElement.TryGetProperty("location", out JsonElement location);
+                                bool hasUnit = argumentsJson.RootElement.TryGetProperty("unit", out JsonElement unit);
+
+                                if (!hasLocation)
+                                {
+                                    throw new ArgumentNullException(nameof(location), "The location argument is required.");
+                                }
+
+                                string functionOutput = hasUnit
+                                    ? GetCurrentWeather(location.GetString(), unit.GetString())
+                                    : GetCurrentWeather(location.GetString());
+                                inputItems.Add(new FunctionCallOutputResponseItem(functionCall.CallId, functionOutput));
+                                break;
+                            }
+
+                        default:
+                            {
+                                // Handle other unexpected calls.
+                                throw new NotImplementedException();
+                            }
+                    }
+
+                    requiresAction = true;
+                    break;
+                }
+            }
+
+            PrintMessageItems(response.OutputItems.OfType<MessageResponseItem>());
+
+        } while (requiresAction);
+    }
+
+    private void PrintMessageItems(IEnumerable<ResponseItem> messageItems)
+    {
+        foreach (MessageResponseItem messageItem in messageItems)
+        {
+            switch (messageItem.Role)
+            {
+                case MessageRole.User:
+                    Console.WriteLine($"[USER]:");
+                    Console.WriteLine($"{messageItem.Content[0].Text}");
+                    Console.WriteLine();
+                    break;
+
+                case MessageRole.Assistant:
+                    Console.WriteLine($"[ASSISTANT]:");
+                    Console.WriteLine($"{messageItem.Content[0].Text}");
+                    Console.WriteLine();
+                    break;
+
+                default:
+                    break;
+            }
+        }
+    }
+}
+
+#pragma warning restore OPENAI001

examples/Responses/Example03_FunctionCallingAsync.cs

@@ -0,0 +1,98 @@
+using NUnit.Framework;
+using OpenAI.Responses;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.Json;
+using System.Threading.Tasks;
+
+namespace OpenAI.Examples;
+
+// This example uses experimental APIs which are subject to change. To use experimental APIs,
+// please acknowledge their experimental status by suppressing the corresponding warning.
+#pragma warning disable OPENAI001
+
+public partial class ResponseExamples
+{
+    // See Example03_FunctionCalling.cs for the tool and function definitions.
+
+    [Test]
+    public async Task Example03_FunctionCallingAsync()
+    {
+        OpenAIResponseClient client = new("gpt-5", Environment.GetEnvironmentVariable("OPENAI_API_KEY"));
+
+        List<ResponseItem> inputItems =
+        [
+            ResponseItem.CreateUserMessageItem("What's the weather like today for my current location?"),
+        ];
+
+        ResponseCreationOptions options = new()
+        {
+            Tools = { getCurrentLocationTool, getCurrentWeatherTool },
+        };
+
+        PrintMessageItems(inputItems.OfType<MessageResponseItem>());
+
+        bool requiresAction;
+
+        do
+        {
+            requiresAction = false;
+            OpenAIResponse response = await client.CreateResponseAsync(inputItems, options);
+
+            inputItems.AddRange(response.OutputItems);
+
+            foreach (ResponseItem outputItem in response.OutputItems)
+            {
+                if (outputItem is FunctionCallResponseItem functionCall)
+                {
+                    switch (functionCall.FunctionName)
+                    {
+                        case nameof(GetCurrentLocation):
+                            {
+                                string functionOutput = GetCurrentLocation();
+                                inputItems.Add(new FunctionCallOutputResponseItem(functionCall.CallId, functionOutput));
+                                break;
+                            }
+
+                        case nameof(GetCurrentWeather):
+                            {
+                                // The arguments that the model wants to use to call the function are specified as a
+                                // stringified JSON object based on the schema defined in the tool definition. Note that
+                                // the model may hallucinate arguments too. Consequently, it is important to do the
+                                // appropriate parsing and validation before calling the function.
+                                using JsonDocument argumentsJson = JsonDocument.Parse(functionCall.FunctionArguments);
+                                bool hasLocation = argumentsJson.RootElement.TryGetProperty("location", out JsonElement location);
+                                bool hasUnit = argumentsJson.RootElement.TryGetProperty("unit", out JsonElement unit);
+
+                                if (!hasLocation)
+                                {
+                                    throw new ArgumentNullException(nameof(location), "The location argument is required.");
+                                }
+
+                                string functionOutput = hasUnit
+                                    ? GetCurrentWeather(location.GetString(), unit.GetString())
+                                    : GetCurrentWeather(location.GetString());
+                                inputItems.Add(new FunctionCallOutputResponseItem(functionCall.CallId, functionOutput));
+                                break;
+                            }
+
+                        default:
+                            {
+                                // Handle other unexpected calls.
+                                throw new NotImplementedException();
+                            }
+                    }
+
+                    requiresAction = true;
+                    break;
+                }
+            }
+
+            PrintMessageItems(response.OutputItems.OfType<MessageResponseItem>());
+
+        } while (requiresAction);
+    }
+}
+
+#pragma warning restore OPENAI001