Use dynamic filtering for extra attributes

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Unreleased
+
+- Filter extra attributes dynamically instead of against a static reserved-key list: `BaseDataBuilder.AddExtraAttributes` now skips any key already set by the builder on the span (`!attributes.ContainsKey(key)`), removing the hard-coded `ReservedAttributeKeys` set so newly added builder attributes are protected automatically ([#107](https://github.com/microsoft/opentelemetry-distro-dotnet/pull/107))
+
 ## 1.0.6 - 2026-07-01
 
 - Make the `invoke_agent` span compliant with OpenTelemetry GenAI semantic conventions v1.42: add request/response GenAI attributes (`gen_ai.request.*`, `gen_ai.data_source.id`, `gen_ai.output.type`, `gen_ai.system_instructions`, `gen_ai.response.finish_reasons`, `gen_ai.usage.*`) via reusable `GenAiRequestParameters`/`GenAiResponseParameters`, and emit `gen_ai.provider.name` on spans that carry agent details (e.g. `invoke_agent`, inference). Token usage is now emitted as integers and `gen_ai.response.finish_reasons` as a string array across all spans ([#120](https://github.com/microsoft/opentelemetry-distro-dotnet/pull/120))

src/Microsoft.OpenTelemetry/Agent365/Runtime/DTOs/Builders/BaseDataBuilder.cs

@@ -31,65 +31,6 @@ protected static T ApplyStatus(T data, Exception? error)
             return data;
         }
 
-        // Reserved attribute keys managed by specific builder methods; extra attributes must NOT override these.
-        private static readonly HashSet<string> ReservedAttributeKeys = new HashSet<string>(StringComparer.Ordinal)
-        {
-            OpenTelemetryConstants.GenAiInputMessagesKey,
-            OpenTelemetryConstants.GenAiOutputMessagesKey,
-            OpenTelemetryConstants.GenAiAgentIdKey,
-            OpenTelemetryConstants.GenAiAgentNameKey,
-            OpenTelemetryConstants.GenAiAgentDescriptionKey,
-            OpenTelemetryConstants.GenAiAgentVersionKey,
-            OpenTelemetryConstants.AgentAUIDKey,
-            OpenTelemetryConstants.AgentEmailKey,
-            OpenTelemetryConstants.AgentBlueprintIdKey,
-            OpenTelemetryConstants.AgentPlatformIdKey,
-            OpenTelemetryConstants.TenantIdKey,
-            OpenTelemetryConstants.GenAiProviderNameKey,
-            OpenTelemetryConstants.ServerAddressKey,
-            OpenTelemetryConstants.ServerPortKey,
-            OpenTelemetryConstants.ChannelNameKey,
-            OpenTelemetryConstants.ChannelLinkKey,
-            OpenTelemetryConstants.UserIdKey,
-            OpenTelemetryConstants.UserEmailKey,
-            OpenTelemetryConstants.UserNameKey,
-            OpenTelemetryConstants.CallerAgentNameKey,
-            OpenTelemetryConstants.CallerAgentIdKey,
-            OpenTelemetryConstants.CallerAgentBlueprintIdKey,
-            OpenTelemetryConstants.CallerAgentAUIDKey,
-            OpenTelemetryConstants.CallerAgentEmailKey,
-            OpenTelemetryConstants.CallerAgentPlatformIdKey,
-            OpenTelemetryConstants.CallerAgentVersionKey,
-            OpenTelemetryConstants.CallerClientIpKey,
-            OpenTelemetryConstants.GenAiConversationIdKey,
-            OpenTelemetryConstants.SessionIdKey,
-            OpenTelemetryConstants.GenAiToolNameKey,
-            OpenTelemetryConstants.GenAiToolArgumentsKey,
-            OpenTelemetryConstants.GenAiToolCallIdKey,
-            OpenTelemetryConstants.GenAiToolDescriptionKey,
-            OpenTelemetryConstants.GenAiToolTypeKey,
-            OpenTelemetryConstants.GenAiToolCallResultKey,
-            OpenTelemetryConstants.GenAiOperationNameKey,
-            OpenTelemetryConstants.GenAiRequestModelKey,
-            OpenTelemetryConstants.GenAiUsageInputTokensKey,
-            OpenTelemetryConstants.GenAiUsageOutputTokensKey,
-            OpenTelemetryConstants.GenAiResponseFinishReasonsKey,
-            OpenTelemetryConstants.GenAiAgentThoughtProcessKey,
-            OpenTelemetryConstants.GenAiDataSourceIdKey,
-            OpenTelemetryConstants.GenAiOutputTypeKey,
-            OpenTelemetryConstants.GenAiRequestChoiceCountKey,
-            OpenTelemetryConstants.GenAiRequestSeedKey,
-            OpenTelemetryConstants.GenAiRequestFrequencyPenaltyKey,
-            OpenTelemetryConstants.GenAiRequestMaxTokensKey,
-            OpenTelemetryConstants.GenAiRequestPresencePenaltyKey,
-            OpenTelemetryConstants.GenAiRequestStopSequencesKey,
-            OpenTelemetryConstants.GenAiRequestTemperatureKey,
-            OpenTelemetryConstants.GenAiRequestTopPKey,
-            OpenTelemetryConstants.GenAiSystemInstructionsKey,
-            OpenTelemetryConstants.GenAiUsageCacheCreationInputTokensKey,
-            OpenTelemetryConstants.GenAiUsageCacheReadInputTokensKey
-        };
-
         /// <summary>
         /// Adds attributes for input messages.
         /// </summary>
@@ -266,15 +207,16 @@ protected static void AddIfNotNull(IDictionary<string, object?> attributes, stri
         }
 
         /// <summary>
-        /// Adds extra attributes to the attributes dictionary while ignoring reserved keys.
+        /// Adds extra attributes to the attributes dictionary.
+        /// Extra attributes cannot override keys already set by the builder on this span.
         /// </summary>
         protected static void AddExtraAttributes(IDictionary<string, object?> attributes, IDictionary<string, object?>? extraAttributes)
         {
             if (extraAttributes == null) return;
 
             foreach (var kvp in extraAttributes)
             {
-                if ((kvp.Value != null && !ReservedAttributeKeys.Contains(kvp.Key)))
+                if (kvp.Value != null && !attributes.ContainsKey(kvp.Key))
                 {
                     attributes[kvp.Key] = kvp.Value;
                 }

test/Microsoft.OpenTelemetry.Agent365.Tests/Runtime/DTOs/Builders/InvokeAgentDataBuilderTests.cs

@@ -471,6 +471,31 @@ public void Build_IgnoresNullValues_InExtraAttributes()
             telemetry.Attributes.Should().ContainKey("custom.good").WhoseValue.Should().Be("ok");
         }
 
+        [TestMethod]
+        public void Build_AllowsRequestModel_ViaExtraAttributes_WhenNotSetByBuilder()
+        {
+            // Arrange
+            var endpoint = new Uri("https://example.com");
+            var agentDetails = new AgentDetails("agent-model", "ModelAgent");
+            var scopeDetails = new InvokeAgentScopeDetails(endpoint: endpoint);
+            var conversationId = "conv-model";
+            var extras = new Dictionary<string, object?>
+            {
+                {OpenTelemetryConstants.GenAiRequestModelKey, "gpt-4o"},
+            };
+
+            // Act
+            var telemetry = InvokeAgentDataBuilder.Build(
+                scopeDetails,
+                agentDetails,
+                conversationId,
+                extraAttributes: extras);
+
+            // Assert - gen_ai.request.model is allowed because InvokeAgentDataBuilder does not set it
+            telemetry.Attributes.Should().ContainKey(OpenTelemetryConstants.GenAiRequestModelKey)
+                .WhoseValue.Should().Be("gpt-4o");
+        }
+
         [TestMethod]
         public void Build_WithAgentPlatformId_SetsExpectedAttributes()
         {