Add openai.api.type telemetry attribute to OpenAI IChatClient implementations

src/Libraries/Microsoft.Extensions.AI.OpenAI/OpenAIChatClient.cs

@@ -87,6 +87,8 @@ public async Task<ChatResponse> GetResponseAsync(
     {
         _ = Throw.IfNull(messages);
 
+        OpenAIClientExtensions.AddOpenAIApiType(OpenAIClientExtensions.OpenAIApiTypeChatCompletions);
+
         var openAIChatMessages = ToOpenAIChatMessages(messages, options);
         var openAIOptions = ToOpenAIOptions(options);
 
@@ -106,6 +108,8 @@ public IAsyncEnumerable<ChatResponseUpdate> GetStreamingResponseAsync(
     {
         _ = Throw.IfNull(messages);
 
+        OpenAIClientExtensions.AddOpenAIApiType(OpenAIClientExtensions.OpenAIApiTypeChatCompletions);
+
         var openAIChatMessages = ToOpenAIChatMessages(messages, options);
         var openAIOptions = ToOpenAIOptions(options);
 

src/Libraries/Microsoft.Extensions.AI.OpenAI/OpenAIClientExtensions.cs

@@ -4,6 +4,7 @@
 using System;
 using System.ClientModel.Primitives;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Net.Mime;
 using System.Text;
@@ -279,4 +280,34 @@ internal sealed class ToolJson
         [JsonExtensionData]
         public Dictionary<string, JsonElement>? ExtensionData { get; set; }
     }
+
+    /// <summary>The "openai.api.type" tag name per the OpenTelemetry semantic conventions for OpenAI.</summary>
+    internal const string OpenAIApiTypeTag = "openai.api.type";
+
+    /// <summary>The "chat_completions" value for the "openai.api.type" tag.</summary>
+    internal const string OpenAIApiTypeChatCompletions = "chat_completions";
+
+    /// <summary>The "responses" value for the "openai.api.type" tag.</summary>
+    internal const string OpenAIApiTypeResponses = "responses";
+
+    /// <summary>The "chat" operation name used by the OpenTelemetry chat client.</summary>
+    private const string ChatOperationName = "chat";
+
+    /// <summary>
+    /// If the current <see cref="Activity"/> represents a "chat" operation span,
+    /// adds the "openai.api.type" tag with the specified value.
+    /// </summary>
+    internal static void AddOpenAIApiType(string apiType)
+    {
+        Activity? activity = Activity.Current;
+        if (activity is { IsAllDataRequested: true })
+        {
+            string name = activity.DisplayName;
+            if (name.StartsWith(ChatOperationName, StringComparison.Ordinal) &&
+                (name.Length == ChatOperationName.Length || name[ChatOperationName.Length] == ' '))
+            {
+                _ = activity.AddTag(OpenAIApiTypeTag, apiType);
+            }
+        }
+    }
 }

src/Libraries/Microsoft.Extensions.AI.OpenAI/OpenAIResponsesChatClient.cs

@@ -92,6 +92,8 @@ public async Task<ChatResponse> GetResponseAsync(
     {
         _ = Throw.IfNull(messages);
 
+        OpenAIClientExtensions.AddOpenAIApiType(OpenAIClientExtensions.OpenAIApiTypeResponses);
+
         // Convert the inputs into what ResponsesClient expects.
         var openAIOptions = AsCreateResponseOptions(options, out string? openAIConversationId);
 
@@ -260,6 +262,8 @@ public IAsyncEnumerable<ChatResponseUpdate> GetStreamingResponseAsync(
     {
         _ = Throw.IfNull(messages);
 
+        OpenAIClientExtensions.AddOpenAIApiType(OpenAIClientExtensions.OpenAIApiTypeResponses);
+
         var openAIOptions = AsCreateResponseOptions(options, out string? openAIConversationId);
         openAIOptions.StreamingEnabled = true;
 

test/Libraries/Microsoft.Extensions.AI.OpenAI.Tests/OpenAIChatClientTests.cs

@@ -6,6 +6,7 @@
 using System.ClientModel.Primitives;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Diagnostics;
 using System.Linq;
 using System.Net.Http;
 using System.Threading.Tasks;
@@ -2010,4 +2011,68 @@ public async Task ReasoningContent_Streaming_SurfacedAsTextReasoningContent()
         // Verify regular content was also captured from the content deltas
         Assert.Equal("9.8 is larger.", string.Concat(updates.Select(u => u.Text)));
     }
+
+    [Theory]
+    [InlineData(false)]
+    [InlineData(true)]
+    public async Task OpenAIApiTypeTag_SetToChatCompletions(bool streaming)
+    {
+        const string Output = """
+            {
+              "id": "chatcmpl-test",
+              "object": "chat.completion",
+              "created": 1727888631,
+              "model": "gpt-4o-mini-2024-07-18",
+              "choices": [
+                {
+                  "index": 0,
+                  "message": {
+                    "role": "assistant",
+                    "content": "Hello!"
+                  },
+                  "finish_reason": "stop"
+                }
+              ],
+              "usage": {
+                "prompt_tokens": 8,
+                "completion_tokens": 2,
+                "total_tokens": 10
+              }
+            }
+            """;
+
+        var sourceName = Guid.NewGuid().ToString();
+        var activities = new List<Activity>();
+        using var listener = new ActivityListener
+        {
+            ShouldListenTo = source => source.Name == sourceName,
+            Sample = (ref ActivityCreationOptions<ActivityContext> _) => ActivitySamplingResult.AllDataAndRecorded,
+            ActivityStopped = activity => activities.Add(activity),
+        };
+        ActivitySource.AddActivityListener(listener);
+
+        using VerbatimHttpHandler handler = new(new HttpHandlerExpectedInput(), Output);
+        using HttpClient httpClient = new(handler);
+        using IChatClient client = new OpenAIClient(new ApiKeyCredential("apikey"), new OpenAIClientOptions { Transport = new HttpClientPipelineTransport(httpClient) })
+            .GetChatClient("gpt-4o-mini")
+            .AsIChatClient()
+            .AsBuilder()
+            .UseOpenTelemetry(sourceName: sourceName)
+            .Build();
+
+        if (streaming)
+        {
+            await foreach (var update in client.GetStreamingResponseAsync("hello"))
+            {
+                // Drain the stream.
+            }
+        }
+        else
+        {
+            await client.GetResponseAsync("hello");
+        }
+
+        var activity = Assert.Single(activities);
+        Assert.Equal("chat_completions", activity.GetTagItem("openai.api.type"));
+    }
 }

test/Libraries/Microsoft.Extensions.AI.OpenAI.Tests/OpenAIResponseClientTests.cs

@@ -6,6 +6,7 @@
 using System.ClientModel.Primitives;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Net.Http;
@@ -6010,6 +6011,75 @@ public async Task ReasoningOptions_NoneValues_ProducesNoReasoningInJson()
         }));
     }
 
+    [Theory]
+    [InlineData(false)]
+    [InlineData(true)]
+    public async Task OpenAIApiTypeTag_SetToResponses(bool streaming)
+    {
+        const string Output = """
+            {
+              "id": "resp_test",
+              "object": "response",
+              "created_at": 1741891428,
+              "status": "completed",
+              "model": "gpt-4o-mini",
+              "output": [
+                {
+                  "id": "msg_test",
+                  "type": "message",
+                  "status": "completed",
+                  "role": "assistant",
+                  "content": [
+                    {
+                      "type": "output_text",
+                      "text": "Hello!"
+                    }
+                  ]
+                }
+              ],
+              "usage": {
+                "input_tokens": 8,
+                "output_tokens": 2,
+                "total_tokens": 10
+              }
+            }
+            """;
+
+        var sourceName = Guid.NewGuid().ToString();
+        var activities = new List<Activity>();
+        using var listener = new ActivityListener
+        {
+            ShouldListenTo = source => source.Name == sourceName,
+            Sample = (ref ActivityCreationOptions<ActivityContext> _) => ActivitySamplingResult.AllDataAndRecorded,
+            ActivityStopped = activity => activities.Add(activity),
+        };
+        ActivitySource.AddActivityListener(listener);
+
+        using VerbatimHttpHandler handler = new(new HttpHandlerExpectedInput(), Output);
+        using HttpClient httpClient = new(handler);
+        using IChatClient client = new OpenAIClient(new ApiKeyCredential("apikey"), new OpenAIClientOptions { Transport = new HttpClientPipelineTransport(httpClient) })
+            .GetResponsesClient("gpt-4o-mini")
+            .AsIChatClient()
+            .AsBuilder()
+            .UseOpenTelemetry(sourceName: sourceName)
+            .Build();
+
+        if (streaming)
+        {
+            await foreach (var update in client.GetStreamingResponseAsync("hello"))
+            {
+                // Drain the stream.
+            }
+        }
+        else
+        {
+            await client.GetResponseAsync("hello");
+        }
+
+        var activity = Assert.Single(activities);
+        Assert.Equal("responses", activity.GetTagItem("openai.api.type"));
+    }
+
     private static IChatClient CreateResponseClient(HttpClient httpClient, string modelId) =>
         new OpenAIClient(
             new ApiKeyCredential("apikey"),