Merge branch 'main' into feature-session-statebag

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/AIContextProviderTests.cs

@@ -19,7 +19,7 @@ public class AIContextProviderTests
     #region InvokingAsync Message Stamping Tests
 
     [Fact]
-    public async Task InvokingAsync_StampsMessagesWithSourceTypeAndSourceAsync()
+    public async Task InvokingAsync_StampsMessagesWithSourceTypeAndSourceIdAsync()
     {
         // Arrange
         var provider = new TestAIContextProviderWithMessages();
@@ -32,18 +32,18 @@ public class AIContextProviderTests
         Assert.NotNull(aiContext.Messages);
         ChatMessage message = aiContext.Messages.Single();
         Assert.NotNull(message.AdditionalProperties);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, sourceType);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-        Assert.Equal(typeof(TestAIContextProviderWithMessages).FullName, source);
+        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+        var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, typedAttribution.SourceType);
+        Assert.Equal(typeof(TestAIContextProviderWithMessages).FullName, typedAttribution.SourceId);
     }
 
     [Fact]
-    public async Task InvokingAsync_WithCustomSourceName_StampsMessagesWithCustomSourceAsync()
+    public async Task InvokingAsync_WithCustomSourceId_StampsMessagesWithCustomSourceIdAsync()
     {
         // Arrange
-        const string CustomSourceName = "CustomContextSource";
-        var provider = new TestAIContextProviderWithCustomSource(CustomSourceName);
+        const string CustomSourceId = "CustomContextSource";
+        var provider = new TestAIContextProviderWithCustomSource(CustomSourceId);
         var context = new AIContextProvider.InvokingContext(s_mockAgent, s_mockSession, [new ChatMessage(ChatRole.User, "Request")]);
 
         // Act
@@ -53,10 +53,10 @@ public class AIContextProviderTests
         Assert.NotNull(aiContext.Messages);
         ChatMessage message = aiContext.Messages.Single();
         Assert.NotNull(message.AdditionalProperties);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, sourceType);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-        Assert.Equal(CustomSourceName, source);
+        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+        var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, typedAttribution.SourceType);
+        Assert.Equal(CustomSourceId, typedAttribution.SourceId);
     }
 
     [Fact]
@@ -73,10 +73,10 @@ public class AIContextProviderTests
         Assert.NotNull(aiContext.Messages);
         ChatMessage message = aiContext.Messages.Single();
         Assert.NotNull(message.AdditionalProperties);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, sourceType);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-        Assert.Equal(typeof(TestAIContextProviderWithPreStampedMessages).FullName, source);
+        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+        var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, typedAttribution.SourceType);
+        Assert.Equal(typeof(TestAIContextProviderWithPreStampedMessages).FullName, typedAttribution.SourceId);
     }
 
     [Fact]
@@ -97,10 +97,10 @@ public class AIContextProviderTests
         foreach (ChatMessage message in messageList)
         {
             Assert.NotNull(message.AdditionalProperties);
-            Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-            Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, sourceType);
-            Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-            Assert.Equal(typeof(TestAIContextProviderWithMultipleMessages).FullName, source);
+            Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+            var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+            Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, typedAttribution.SourceType);
+            Assert.Equal(typeof(TestAIContextProviderWithMultipleMessages).FullName, typedAttribution.SourceId);
         }
     }
 
@@ -473,7 +473,7 @@ public class AIContextProviderTests
 
     private sealed class TestAIContextProviderWithCustomSource : AIContextProvider
     {
-        public TestAIContextProviderWithCustomSource(string sourceName) : base(sourceName)
+        public TestAIContextProviderWithCustomSource(string sourceId) : base(sourceId)
         {
         }
 
@@ -491,8 +491,7 @@ public class AIContextProviderTests
             var message = new ChatMessage(ChatRole.System, "Pre-stamped Message");
             message.AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                [AgentRequestMessageSourceType.AdditionalPropertiesKey] = AgentRequestMessageSourceType.AIContextProvider,
-                [AgentRequestMessageSource.AdditionalPropertiesKey] = this.GetType().FullName!
+                [AgentRequestMessageSourceAttribution.AdditionalPropertiesKey] = new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.AIContextProvider, this.GetType().FullName!)
             };
             return new(new AIContext
             {

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/AgentRequestMessageSourceAttributionTests.cs

@@ -0,0 +1,466 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+namespace Microsoft.Agents.AI.Abstractions.UnitTests;
+
+/// <summary>
+/// Contains tests for the <see cref="AgentRequestMessageSourceAttribution"/> struct.
+/// </summary>
+public sealed class AgentRequestMessageSourceAttributionTests
+{
+    #region Constructor Tests
+
+    [Fact]
+    public void Constructor_SetsSourceTypeAndSourceId()
+    {
+        // Arrange
+        AgentRequestMessageSourceType expectedType = AgentRequestMessageSourceType.AIContextProvider;
+        const string ExpectedId = "MyProvider";
+
+        // Act
+        AgentRequestMessageSourceAttribution attribution = new(expectedType, ExpectedId);
+
+        // Assert
+        Assert.Equal(expectedType, attribution.SourceType);
+        Assert.Equal(ExpectedId, attribution.SourceId);
+    }
+
+    [Fact]
+    public void Constructor_WithNullSourceId_SetsNullSourceId()
+    {
+        // Arrange
+        AgentRequestMessageSourceType sourceType = AgentRequestMessageSourceType.ChatHistory;
+
+        // Act
+        AgentRequestMessageSourceAttribution attribution = new(sourceType, null);
+
+        // Assert
+        Assert.Equal(sourceType, attribution.SourceType);
+        Assert.Null(attribution.SourceId);
+    }
+
+    #endregion
+
+    #region AdditionalPropertiesKey Tests
+
+    [Fact]
+    public void AdditionalPropertiesKey_IsAttribution()
+    {
+        // Assert
+        Assert.Equal("_attribution", AgentRequestMessageSourceAttribution.AdditionalPropertiesKey);
+    }
+
+    #endregion
+
+    #region Default Value Tests
+
+    [Fact]
+    public void Default_HasDefaultSourceTypeAndNullSourceId()
+    {
+        // Arrange & Act
+        AgentRequestMessageSourceAttribution attribution = default;
+
+        // Assert
+        Assert.Equal(default, attribution.SourceType);
+        Assert.Null(attribution.SourceId);
+    }
+
+    #endregion
+
+    #region Equals (IEquatable) Tests
+
+    [Fact]
+    public void Equals_WithSameSourceTypeAndSourceId_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void Equals_WithDifferentSourceType_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.ChatHistory, "Provider1");
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void Equals_WithDifferentSourceId_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider2");
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void Equals_WithDifferentSourceTypeAndSourceId_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.ChatHistory, "Provider2");
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void Equals_WithDifferentCaseSourceId_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "provider");
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void Equals_BothDefaultValues_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = default;
+        AgentRequestMessageSourceAttribution attribution2 = default;
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void Equals_WithBothNullSourceIds_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.External, null!);
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.External, null!);
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void Equals_WithOneNullSourceId_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.External, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.External, null!);
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    #endregion
+
+    #region Object.Equals Tests
+
+    [Fact]
+    public void ObjectEquals_WithEqualAttribution_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.ChatHistory, "Provider");
+        object attribution2 = new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "Provider");
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void ObjectEquals_WithDifferentType_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution = new(AgentRequestMessageSourceType.ChatHistory, "Provider");
+        object other = "NotAnAttribution";
+
+        // Act
+        bool result = attribution.Equals(other);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void ObjectEquals_WithNullObject_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution = new(AgentRequestMessageSourceType.ChatHistory, "Provider");
+        object? other = null;
+
+        // Act
+        bool result = attribution.Equals(other);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void ObjectEquals_WithBoxedDifferentAttribution_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.ChatHistory, "Provider1");
+        object attribution2 = new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "Provider2");
+
+        // Act
+        bool result = attribution1.Equals(attribution2);
+
+        // Assert
+        Assert.False(result);
+    }
+
+    #endregion
+
+    #region GetHashCode Tests
+
+    [Fact]
+    public void GetHashCode_WithSameValues_ReturnsSameHashCode()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+
+        // Act
+        int hashCode1 = attribution1.GetHashCode();
+        int hashCode2 = attribution2.GetHashCode();
+
+        // Assert
+        Assert.Equal(hashCode1, hashCode2);
+    }
+
+    [Fact]
+    public void GetHashCode_WithDifferentSourceType_ReturnsDifferentHashCode()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.ChatHistory, "Provider");
+
+        // Act
+        int hashCode1 = attribution1.GetHashCode();
+        int hashCode2 = attribution2.GetHashCode();
+
+        // Assert
+        Assert.NotEqual(hashCode1, hashCode2);
+    }
+
+    [Fact]
+    public void GetHashCode_WithDifferentSourceId_ReturnsDifferentHashCode()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider2");
+
+        // Act
+        int hashCode1 = attribution1.GetHashCode();
+        int hashCode2 = attribution2.GetHashCode();
+
+        // Assert
+        Assert.NotEqual(hashCode1, hashCode2);
+    }
+
+    [Fact]
+    public void GetHashCode_ConsistentWithEquals()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.External, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.External, "Provider");
+
+        // Act & Assert
+        Assert.True(attribution1.Equals(attribution2));
+        Assert.Equal(attribution1.GetHashCode(), attribution2.GetHashCode());
+    }
+
+    [Fact]
+    public void GetHashCode_WithNullSourceId_DoesNotThrow()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution = new(AgentRequestMessageSourceType.External, null!);
+
+        // Act
+        int hashCode = attribution.GetHashCode();
+
+        // Assert
+        Assert.IsType<int>(hashCode);
+    }
+
+    #endregion
+
+    #region Equality Operator Tests
+
+    [Fact]
+    public void EqualityOperator_WithEqualValues_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+
+        // Act
+        bool result = attribution1 == attribution2;
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void EqualityOperator_WithDifferentValues_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.ChatHistory, "Provider2");
+
+        // Act
+        bool result = attribution1 == attribution2;
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void EqualityOperator_WithBothDefault_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = default;
+        AgentRequestMessageSourceAttribution attribution2 = default;
+
+        // Act
+        bool result = attribution1 == attribution2;
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void EqualityOperator_WithDifferentSourceTypeOnly_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.External, "Provider");
+
+        // Act
+        bool result = attribution1 == attribution2;
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void EqualityOperator_WithDifferentSourceIdOnly_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider2");
+
+        // Act
+        bool result = attribution1 == attribution2;
+
+        // Assert
+        Assert.False(result);
+    }
+
+    #endregion
+
+    #region Inequality Operator Tests
+
+    [Fact]
+    public void InequalityOperator_WithEqualValues_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+
+        // Act
+        bool result = attribution1 != attribution2;
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void InequalityOperator_WithDifferentValues_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.ChatHistory, "Provider2");
+
+        // Act
+        bool result = attribution1 != attribution2;
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void InequalityOperator_WithBothDefault_ReturnsFalse()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = default;
+        AgentRequestMessageSourceAttribution attribution2 = default;
+
+        // Act
+        bool result = attribution1 != attribution2;
+
+        // Assert
+        Assert.False(result);
+    }
+
+    [Fact]
+    public void InequalityOperator_WithDifferentSourceTypeOnly_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.External, "Provider");
+
+        // Act
+        bool result = attribution1 != attribution2;
+
+        // Assert
+        Assert.True(result);
+    }
+
+    [Fact]
+    public void InequalityOperator_WithDifferentSourceIdOnly_ReturnsTrue()
+    {
+        // Arrange
+        AgentRequestMessageSourceAttribution attribution1 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider1");
+        AgentRequestMessageSourceAttribution attribution2 = new(AgentRequestMessageSourceType.AIContextProvider, "Provider2");
+
+        // Act
+        bool result = attribution1 != attribution2;
+
+        // Assert
+        Assert.True(result);
+    }
+
+    #endregion
+}

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/AgentRequestMessageSourceTypeTests.cs

@@ -5,7 +5,7 @@ using System;
 namespace Microsoft.Agents.AI.Abstractions.UnitTests;
 
 /// <summary>
-/// Contains tests for the <see cref="AgentRequestMessageSourceType"/> class.
+/// Contains tests for the <see cref="AgentRequestMessageSourceType"/> struct.
 /// </summary>
 public sealed class AgentRequestMessageSourceTypeTests
 {
@@ -38,6 +38,16 @@ public sealed class AgentRequestMessageSourceTypeTests
         Assert.Throws<ArgumentException>(() => new AgentRequestMessageSourceType(string.Empty));
     }
 
+    [Fact]
+    public void Default_DefaultsToExternal()
+    {
+        // Act
+        AgentRequestMessageSourceType defaultSource = default;
+
+        // Assert
+        Assert.Equal(AgentRequestMessageSourceType.External, defaultSource);
+    }
+
     #endregion
 
     #region Static Properties Tests
@@ -49,7 +59,6 @@ public sealed class AgentRequestMessageSourceTypeTests
         AgentRequestMessageSourceType source = AgentRequestMessageSourceType.External;
 
         // Assert
-        Assert.NotNull(source);
         Assert.Equal("External", source.Value);
     }
 
@@ -60,7 +69,6 @@ public sealed class AgentRequestMessageSourceTypeTests
         AgentRequestMessageSourceType source = AgentRequestMessageSourceType.AIContextProvider;
 
         // Assert
-        Assert.NotNull(source);
         Assert.Equal("AIContextProvider", source.Value);
     }
 
@@ -71,22 +79,11 @@ public sealed class AgentRequestMessageSourceTypeTests
         AgentRequestMessageSourceType source = AgentRequestMessageSourceType.ChatHistory;
 
         // Assert
-        Assert.NotNull(source);
         Assert.Equal("ChatHistory", source.Value);
     }
 
     [Fact]
-    public void AdditionalPropertiesKey_ReturnsExpectedValue()
-    {
-        // Arrange & Act
-        string key = AgentRequestMessageSourceType.AdditionalPropertiesKey;
-
-        // Assert
-        Assert.Equal("Agent.RequestMessageSourceType", key);
-    }
-
-    [Fact]
-    public void StaticProperties_ReturnSameInstanceOnMultipleCalls()
+    public void StaticProperties_ReturnEqualValuesOnMultipleCalls()
     {
         // Arrange & Act
         AgentRequestMessageSourceType external1 = AgentRequestMessageSourceType.External;
@@ -97,9 +94,9 @@ public sealed class AgentRequestMessageSourceTypeTests
         AgentRequestMessageSourceType chatHistory2 = AgentRequestMessageSourceType.ChatHistory;
 
         // Assert
-        Assert.Same(external1, external2);
-        Assert.Same(aiContextProvider1, aiContextProvider2);
-        Assert.Same(chatHistory1, chatHistory2);
+        Assert.Equal(external1, external2);
+        Assert.Equal(aiContextProvider1, aiContextProvider2);
+        Assert.Equal(chatHistory1, chatHistory2);
     }
 
     #endregion
@@ -148,7 +145,7 @@ public sealed class AgentRequestMessageSourceTypeTests
     }
 
     [Fact]
-    public void Equals_WithNull_ReturnsFalse()
+    public void Equals_WithNullObject_ReturnsFalse()
     {
         // Arrange
         AgentRequestMessageSourceType source = new("Test");
@@ -314,11 +311,11 @@ public sealed class AgentRequestMessageSourceTypeTests
     }
 
     [Fact]
-    public void EqualityOperator_WithBothNull_ReturnsTrue()
+    public void EqualityOperator_WithDefaultValues_ReturnsTrue()
     {
         // Arrange
-        AgentRequestMessageSourceType? source1 = null;
-        AgentRequestMessageSourceType? source2 = null;
+        AgentRequestMessageSourceType source1 = default;
+        AgentRequestMessageSourceType source2 = default;
 
         // Act
         bool result = source1 == source2;
@@ -327,34 +324,6 @@ public sealed class AgentRequestMessageSourceTypeTests
         Assert.True(result);
     }
 
-    [Fact]
-    public void EqualityOperator_WithLeftNull_ReturnsFalse()
-    {
-        // Arrange
-        AgentRequestMessageSourceType? source1 = null;
-        AgentRequestMessageSourceType source2 = new("Test");
-
-        // Act
-        bool result = source1 == source2;
-
-        // Assert
-        Assert.False(result);
-    }
-
-    [Fact]
-    public void EqualityOperator_WithRightNull_ReturnsFalse()
-    {
-        // Arrange
-        AgentRequestMessageSourceType source1 = new("Test");
-        AgentRequestMessageSourceType? source2 = null;
-
-        // Act
-        bool result = source1 == source2;
-
-        // Assert
-        Assert.False(result);
-    }
-
     [Fact]
     public void EqualityOperator_WithStaticInstances_ReturnsTrue()
     {
@@ -416,11 +385,11 @@ public sealed class AgentRequestMessageSourceTypeTests
     }
 
     [Fact]
-    public void InequalityOperator_WithBothNull_ReturnsFalse()
+    public void InequalityOperator_WithBothDefault_ReturnsFalse()
     {
         // Arrange
-        AgentRequestMessageSourceType? source1 = null;
-        AgentRequestMessageSourceType? source2 = null;
+        AgentRequestMessageSourceType source1 = default;
+        AgentRequestMessageSourceType source2 = default;
 
         // Act
         bool result = source1 != source2;
@@ -429,34 +398,6 @@ public sealed class AgentRequestMessageSourceTypeTests
         Assert.False(result);
     }
 
-    [Fact]
-    public void InequalityOperator_WithLeftNull_ReturnsTrue()
-    {
-        // Arrange
-        AgentRequestMessageSourceType? source1 = null;
-        AgentRequestMessageSourceType source2 = new("Test");
-
-        // Act
-        bool result = source1 != source2;
-
-        // Assert
-        Assert.True(result);
-    }
-
-    [Fact]
-    public void InequalityOperator_WithRightNull_ReturnsTrue()
-    {
-        // Arrange
-        AgentRequestMessageSourceType source1 = new("Test");
-        AgentRequestMessageSourceType? source2 = null;
-
-        // Act
-        bool result = source1 != source2;
-
-        // Assert
-        Assert.True(result);
-    }
-
     [Fact]
     public void InequalityOperator_DifferentStaticInstances_ReturnsTrue()
     {

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/ChatHistoryProviderExtensionsTests.cs

@@ -64,7 +64,7 @@ public sealed class ChatHistoryProviderExtensionsTests
         Mock<ChatHistoryProvider> providerMock = new();
         List<ChatMessage> requestMessages =
         [
-            new(ChatRole.System, "System") { AdditionalProperties = new() { { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.ChatHistory } } },
+            new(ChatRole.System, "System") { AdditionalProperties = new() { { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "TestSource") } } },
             new(ChatRole.User, "Hello")
         ];
         ChatHistoryProvider.InvokedContext context = new(s_mockAgent, s_mockSession, requestMessages)
@@ -114,9 +114,9 @@ public sealed class ChatHistoryProviderExtensionsTests
         Mock<ChatHistoryProvider> providerMock = new();
         List<ChatMessage> requestMessages =
         [
-            new(ChatRole.System, "System") { AdditionalProperties = new() { { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.ChatHistory } } },
+            new(ChatRole.System, "System") { AdditionalProperties = new() { { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "TestSource") } } },
             new(ChatRole.User, "Hello"),
-            new(ChatRole.System, "Context") { AdditionalProperties = new() { { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.AIContextProvider } } }
+            new(ChatRole.System, "Context") { AdditionalProperties = new() { { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.AIContextProvider, "TestContextSource") } } }
         ];
         ChatHistoryProvider.InvokedContext context = new(s_mockAgent, s_mockSession, requestMessages);
 

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/ChatHistoryProviderMessageFilterTests.cs

@@ -170,7 +170,7 @@ public sealed class ChatHistoryProviderMessageFilterTests
         var innerProviderMock = new Mock<ChatHistoryProvider>();
         List<ChatMessage> requestMessages =
         [
-            new(ChatRole.System, "System") { AdditionalProperties = new() { { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.ChatHistory } } },
+            new(ChatRole.System, "System") { AdditionalProperties = new() { { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "TestSource") } } },
             new(ChatRole.User, "Hello"),
         ];
         var responseMessages = new List<ChatMessage> { new(ChatRole.Assistant, "Response") };
@@ -189,7 +189,7 @@ public sealed class ChatHistoryProviderMessageFilterTests
         // Filter that modifies the context
         ChatHistoryProvider.InvokedContext InvokedFilter(ChatHistoryProvider.InvokedContext ctx)
         {
-            var modifiedRequestMessages = ctx.RequestMessages.Where(x => x.GetAgentRequestMessageSource() == AgentRequestMessageSourceType.External).Select(m => new ChatMessage(m.Role, $"[FILTERED] {m.Text}")).ToList();
+            var modifiedRequestMessages = ctx.RequestMessages.Where(x => x.GetAgentRequestMessageSourceType() == AgentRequestMessageSourceType.External).Select(m => new ChatMessage(m.Role, $"[FILTERED] {m.Text}")).ToList();
             return new ChatHistoryProvider.InvokedContext(s_mockAgent, s_mockSession, modifiedRequestMessages)
             {
                 ResponseMessages = ctx.ResponseMessages,

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/ChatHistoryProviderTests.cs

@@ -21,7 +21,7 @@ public class ChatHistoryProviderTests
     #region InvokingAsync Message Stamping Tests
 
     [Fact]
-    public async Task InvokingAsync_StampsMessagesWithSourceTypeAndSourceAsync()
+    public async Task InvokingAsync_StampsMessagesWithSourceTypeAndSourceIdAsync()
     {
         // Arrange
         var provider = new TestChatHistoryProvider();
@@ -33,18 +33,18 @@ public class ChatHistoryProviderTests
         // Assert
         ChatMessage message = messages.Single();
         Assert.NotNull(message.AdditionalProperties);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-        Assert.Equal(AgentRequestMessageSourceType.ChatHistory, sourceType);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-        Assert.Equal(typeof(TestChatHistoryProvider).FullName, source);
+        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+        var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+        Assert.Equal(AgentRequestMessageSourceType.ChatHistory, typedAttribution.SourceType);
+        Assert.Equal(typeof(TestChatHistoryProvider).FullName, typedAttribution.SourceId);
     }
 
     [Fact]
-    public async Task InvokingAsync_WithCustomSourceName_StampsMessagesWithCustomSourceAsync()
+    public async Task InvokingAsync_WithCustomSourceId_StampsMessagesWithCustomSourceIdAsync()
     {
         // Arrange
-        const string CustomSourceName = "CustomHistorySource";
-        var provider = new TestChatHistoryProviderWithCustomSource(CustomSourceName);
+        const string CustomSourceId = "CustomHistorySource";
+        var provider = new TestChatHistoryProviderWithCustomSource(CustomSourceId);
         var context = new ChatHistoryProvider.InvokingContext(s_mockAgent, s_mockSession, [new ChatMessage(ChatRole.User, "Request")]);
 
         // Act
@@ -53,10 +53,10 @@ public class ChatHistoryProviderTests
         // Assert
         ChatMessage message = messages.Single();
         Assert.NotNull(message.AdditionalProperties);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-        Assert.Equal(AgentRequestMessageSourceType.ChatHistory, sourceType);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-        Assert.Equal(CustomSourceName, source);
+        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+        var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+        Assert.Equal(AgentRequestMessageSourceType.ChatHistory, typedAttribution.SourceType);
+        Assert.Equal(CustomSourceId, typedAttribution.SourceId);
     }
 
     [Fact]
@@ -72,10 +72,10 @@ public class ChatHistoryProviderTests
         // Assert
         ChatMessage message = messages.Single();
         Assert.NotNull(message.AdditionalProperties);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-        Assert.Equal(AgentRequestMessageSourceType.ChatHistory, sourceType);
-        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-        Assert.Equal(typeof(TestChatHistoryProviderWithPreStampedMessages).FullName, source);
+        Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+        var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+        Assert.Equal(AgentRequestMessageSourceType.ChatHistory, typedAttribution.SourceType);
+        Assert.Equal(typeof(TestChatHistoryProviderWithPreStampedMessages).FullName, typedAttribution.SourceId);
     }
 
     [Fact]
@@ -95,10 +95,10 @@ public class ChatHistoryProviderTests
         foreach (ChatMessage message in messageList)
         {
             Assert.NotNull(message.AdditionalProperties);
-            Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceType.AdditionalPropertiesKey, out object? sourceType));
-            Assert.Equal(AgentRequestMessageSourceType.ChatHistory, sourceType);
-            Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSource.AdditionalPropertiesKey, out object? source));
-            Assert.Equal(typeof(TestChatHistoryProviderWithMultipleMessages).FullName, source);
+            Assert.True(message.AdditionalProperties.TryGetValue(AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, out object? attribution));
+            var typedAttribution = Assert.IsType<AgentRequestMessageSourceAttribution>(attribution);
+            Assert.Equal(AgentRequestMessageSourceType.ChatHistory, typedAttribution.SourceType);
+            Assert.Equal(typeof(TestChatHistoryProviderWithMultipleMessages).FullName, typedAttribution.SourceId);
         }
     }
 
@@ -379,7 +379,7 @@ public class ChatHistoryProviderTests
 
     private sealed class TestChatHistoryProviderWithCustomSource : ChatHistoryProvider
     {
-        public TestChatHistoryProviderWithCustomSource(string sourceName) : base(sourceName)
+        public TestChatHistoryProviderWithCustomSource(string sourceId) : base(sourceId)
         {
         }
 
@@ -397,8 +397,7 @@ public class ChatHistoryProviderTests
             var message = new ChatMessage(ChatRole.User, "Pre-stamped Message");
             message.AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                [AgentRequestMessageSourceType.AdditionalPropertiesKey] = AgentRequestMessageSourceType.ChatHistory,
-                [AgentRequestMessageSource.AdditionalPropertiesKey] = this.GetType().FullName!
+                [AgentRequestMessageSourceAttribution.AdditionalPropertiesKey] = new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, this.GetType().FullName!)
             };
             return new([message]);
         }

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/ChatMessageExtensionsTests.cs

@@ -9,23 +9,23 @@ namespace Microsoft.Agents.AI.Abstractions.UnitTests;
 /// </summary>
 public sealed class ChatMessageExtensionsTests
 {
-    #region GetAgentRequestMessageSource Tests
+    #region GetAgentRequestMessageSourceType Tests
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithNoAdditionalProperties_ReturnsExternal()
+    public void GetAgentRequestMessageSourceType_WithNoAdditionalProperties_ReturnsExternal()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello");
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.External, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithNullAdditionalProperties_ReturnsExternal()
+    public void GetAgentRequestMessageSourceType_WithNullAdditionalProperties_ReturnsExternal()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
@@ -34,14 +34,14 @@ public sealed class ChatMessageExtensionsTests
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.External, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithEmptyAdditionalProperties_ReturnsExternal()
+    public void GetAgentRequestMessageSourceType_WithEmptyAdditionalProperties_ReturnsExternal()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
@@ -50,130 +50,130 @@ public sealed class ChatMessageExtensionsTests
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.External, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithExternalSource_ReturnsExternal()
+    public void GetAgentRequestMessageSourceType_WithExternalSourceType_ReturnsExternal()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
         {
             AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.External }
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.External, "TestSourceId") }
             }
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.External, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithAIContextProviderSource_ReturnsAIContextProvider()
+    public void GetAgentRequestMessageSourceType_WithAIContextProviderSourceType_ReturnsAIContextProvider()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
         {
             AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.AIContextProvider }
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.AIContextProvider, "TestSourceId") }
             }
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithChatHistorySource_ReturnsChatHistory()
+    public void GetAgentRequestMessageSourceType_WithChatHistorySourceType_ReturnsChatHistory()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
         {
             AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.ChatHistory }
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "TestSourceId") }
             }
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.ChatHistory, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithCustomSource_ReturnsCustomSource()
+    public void GetAgentRequestMessageSourceType_WithCustomSourceType_ReturnsCustomSourceType()
     {
         // Arrange
-        AgentRequestMessageSourceType customSource = new("CustomSource");
+        AgentRequestMessageSourceType customSourceType = new("CustomSourceType");
         ChatMessage message = new(ChatRole.User, "Hello")
         {
             AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                { AgentRequestMessageSourceType.AdditionalPropertiesKey, customSource }
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(customSourceType, "TestSourceId") }
             }
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
-        Assert.Equal(customSource, result);
-        Assert.Equal("CustomSource", result.Value);
+        Assert.Equal(customSourceType, result);
+        Assert.Equal("CustomSourceType", result.Value);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithWrongKeyType_ReturnsExternal()
+    public void GetAgentRequestMessageSourceType_WithWrongAttributionType_ReturnsExternal()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
         {
             AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                { AgentRequestMessageSourceType.AdditionalPropertiesKey, "NotAnAgentRequestMessageSource" }
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, "NotAnAgentRequestMessageSourceAttribution" }
             }
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.External, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithNullValue_ReturnsExternal()
+    public void GetAgentRequestMessageSourceType_WithNullAttributionValue_ReturnsExternal()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
         {
             AdditionalProperties = new AdditionalPropertiesDictionary
             {
-                { AgentRequestMessageSourceType.AdditionalPropertiesKey, null! }
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, null! }
             }
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.External, result);
     }
 
     [Fact]
-    public void GetAgentRequestMessageSource_WithMultipleProperties_ReturnsCorrectSource()
+    public void GetAgentRequestMessageSourceType_WithMultipleProperties_ReturnsCorrectSourceType()
     {
         // Arrange
         ChatMessage message = new(ChatRole.User, "Hello")
@@ -181,17 +181,345 @@ public sealed class ChatMessageExtensionsTests
             AdditionalProperties = new AdditionalPropertiesDictionary
             {
                 { "OtherProperty", "SomeValue" },
-                { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.ChatHistory },
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "TestSourceId") },
                 { "AnotherProperty", 123 }
             }
         };
 
         // Act
-        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSource();
+        AgentRequestMessageSourceType result = message.GetAgentRequestMessageSourceType();
 
         // Assert
         Assert.Equal(AgentRequestMessageSourceType.ChatHistory, result);
     }
 
     #endregion
+
+    #region GetAgentRequestMessageSourceId Tests
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithNoAdditionalProperties_ReturnsNull()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello");
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithNullAdditionalProperties_ReturnsNull()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = null
+        };
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithEmptyAdditionalProperties_ReturnsNull()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary()
+        };
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithAttribution_ReturnsSourceId()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.AIContextProvider, "MyProvider.FullName") }
+            }
+        };
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Equal("MyProvider.FullName", result);
+    }
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithDifferentSourceIds_ReturnsCorrectSourceId()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "CustomHistorySourceId") }
+            }
+        };
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Equal("CustomHistorySourceId", result);
+    }
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithWrongAttributionType_ReturnsNull()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, "NotAnAgentRequestMessageSourceAttribution" }
+            }
+        };
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithNullAttributionValue_ReturnsNull()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, null! }
+            }
+        };
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void GetAgentRequestMessageSourceId_WithMultipleProperties_ReturnsCorrectSourceId()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { "OtherProperty", "SomeValue" },
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.External, "ExpectedSourceId") },
+                { "AnotherProperty", 123 }
+            }
+        };
+
+        // Act
+        string? result = message.GetAgentRequestMessageSourceId();
+
+        // Assert
+        Assert.Equal("ExpectedSourceId", result);
+    }
+
+    #endregion
+
+    #region AsAgentRequestMessageSourcedMessage Tests
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithNoAdditionalProperties_ReturnsClonesMessageWithAttribution()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello");
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.External, "TestSourceId");
+
+        // Assert
+        Assert.NotSame(message, result);
+        Assert.Equal(AgentRequestMessageSourceType.External, result.GetAgentRequestMessageSourceType());
+        Assert.Equal("TestSourceId", result.GetAgentRequestMessageSourceId());
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithNullAdditionalProperties_ReturnsClonesMessageWithAttribution()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = null
+        };
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.AIContextProvider, "ProviderSourceId");
+
+        // Assert
+        Assert.NotSame(message, result);
+        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, result.GetAgentRequestMessageSourceType());
+        Assert.Equal("ProviderSourceId", result.GetAgentRequestMessageSourceId());
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithMatchingSourceTypeAndSourceId_ReturnsSameInstance()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "HistoryId") }
+            }
+        };
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.ChatHistory, "HistoryId");
+
+        // Assert
+        Assert.Same(message, result);
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithDifferentSourceType_ReturnsClonesMessageWithNewAttribution()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.External, "SourceId") }
+            }
+        };
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.AIContextProvider, "SourceId");
+
+        // Assert
+        Assert.NotSame(message, result);
+        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, result.GetAgentRequestMessageSourceType());
+        Assert.Equal("SourceId", result.GetAgentRequestMessageSourceId());
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithDifferentSourceId_ReturnsClonesMessageWithNewAttribution()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.External, "OriginalId") }
+            }
+        };
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.External, "NewId");
+
+        // Assert
+        Assert.NotSame(message, result);
+        Assert.Equal(AgentRequestMessageSourceType.External, result.GetAgentRequestMessageSourceType());
+        Assert.Equal("NewId", result.GetAgentRequestMessageSourceId());
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithDefaultNullSourceId_ReturnsClonesMessageWithNullSourceId()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello");
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.ChatHistory);
+
+        // Assert
+        Assert.NotSame(message, result);
+        Assert.Equal(AgentRequestMessageSourceType.ChatHistory, result.GetAgentRequestMessageSourceType());
+        Assert.Null(result.GetAgentRequestMessageSourceId());
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithMatchingSourceTypeAndNullSourceId_ReturnsSameInstance()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.External, null) }
+            }
+        };
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.External);
+
+        // Assert
+        Assert.Same(message, result);
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_DoesNotModifyOriginalMessage()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello");
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.AIContextProvider, "ProviderId");
+
+        // Assert
+        Assert.Null(message.AdditionalProperties);
+        Assert.NotNull(result.AdditionalProperties);
+        Assert.Equal(AgentRequestMessageSourceType.AIContextProvider, result.GetAgentRequestMessageSourceType());
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_WithWrongAttributionType_ReturnsClonesMessageWithNewAttribution()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.User, "Hello")
+        {
+            AdditionalProperties = new AdditionalPropertiesDictionary
+            {
+                { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, "NotAnAttribution" }
+            }
+        };
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.External, "SourceId");
+
+        // Assert
+        Assert.NotSame(message, result);
+        Assert.Equal(AgentRequestMessageSourceType.External, result.GetAgentRequestMessageSourceType());
+        Assert.Equal("SourceId", result.GetAgentRequestMessageSourceId());
+    }
+
+    [Fact]
+    public void AsAgentRequestMessageSourcedMessage_PreservesMessageContent()
+    {
+        // Arrange
+        ChatMessage message = new(ChatRole.Assistant, "Test content");
+
+        // Act
+        ChatMessage result = message.AsAgentRequestMessageSourcedMessage(AgentRequestMessageSourceType.ChatHistory, "HistoryId");
+
+        // Assert
+        Assert.Equal(ChatRole.Assistant, result.Role);
+        Assert.Equal("Test content", result.Text);
+    }
+
+    #endregion
 }

dotnet/tests/Microsoft.Agents.AI.Abstractions.UnitTests/InMemoryChatHistoryProviderTests.cs

@@ -71,7 +71,7 @@ public class InMemoryChatHistoryProviderTests
         var requestMessages = new List<ChatMessage>
         {
             new(ChatRole.User, "Hello"),
-            new(ChatRole.System, "additional context") { AdditionalProperties = new() { { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.ChatHistory } } },
+            new(ChatRole.System, "additional context") { AdditionalProperties = new() { { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.ChatHistory, "TestSource") } } },
         };
         var responseMessages = new List<ChatMessage>
         {

dotnet/tests/Microsoft.Agents.AI.CosmosNoSql.UnitTests/CosmosChatHistoryProviderTests.cs

@@ -302,7 +302,7 @@ public sealed class CosmosChatHistoryProviderTests : IAsyncLifetime, IDisposable
             new ChatMessage(ChatRole.User, "First message"),
             new ChatMessage(ChatRole.Assistant, "Second message"),
             new ChatMessage(ChatRole.User, "Third message"),
-            new ChatMessage(ChatRole.System, "System context message") { AdditionalProperties = new() { { AgentRequestMessageSourceType.AdditionalPropertiesKey, AgentRequestMessageSourceType.AIContextProvider } } }
+            new ChatMessage(ChatRole.System, "System context message") { AdditionalProperties = new() { { AgentRequestMessageSourceAttribution.AdditionalPropertiesKey, new AgentRequestMessageSourceAttribution(AgentRequestMessageSourceType.AIContextProvider, "TestSource") } } }
         };
         var responseMessages = new[]
         {

dotnet/tests/Microsoft.Agents.AI.Purview.UnitTests/PurviewClientTests.cs

@@ -478,7 +478,7 @@ public sealed class PurviewClientTests : IDisposable
     private static ContentToProcess CreateValidContentToProcess()
     {
         var content = new PurviewTextContent("Test content");
-        var metadata = new ProcessConversationMetadata(content, "msg-123", false, "Test message");
+        var metadata = new ProcessConversationMetadata(content, "msg-123", false, "Test message", "test-correlation-id");
         var activityMetadata = new ActivityMetadata(Activity.UploadText);
         var deviceMetadata = new DeviceMetadata
         {

dotnet/tests/Microsoft.Agents.AI.UnitTests/ChatClient/ChatClientAgentTests.cs

@@ -1320,6 +1320,45 @@ public partial class ChatClientAgentTests
         Assert.Equal("what?", historyMessages[1].Text);
     }
 
+    /// <summary>
+    /// Verify that RunStreamingAsync includes chat history in messages sent to the chat client on subsequent calls.
+    /// </summary>
+    [Fact]
+    public async Task RunStreamingAsyncIncludesChatHistoryInMessagesToChatClientAsync()
+    {
+        // Arrange
+        List<IEnumerable<ChatMessage>> capturedMessages = [];
+        Mock<IChatClient> mockService = new();
+        ChatResponseUpdate[] returnUpdates =
+            [
+                new ChatResponseUpdate(role: ChatRole.Assistant, content: "response"),
+            ];
+        mockService.Setup(
+            s => s.GetStreamingResponseAsync(
+                It.IsAny<IEnumerable<ChatMessage>>(),
+                It.IsAny<ChatOptions>(),
+                It.IsAny<CancellationToken>()))
+            .Returns(ToAsyncEnumerableAsync(returnUpdates))
+            .Callback<IEnumerable<ChatMessage>, ChatOptions?, CancellationToken>((msgs, _, _) => capturedMessages.Add(msgs.ToList()));
+        ChatClientAgent agent = new(mockService.Object, options: new()
+        {
+            ChatOptions = new() { Instructions = "test instructions" },
+        });
+
+        // Act
+        ChatClientAgentSession? session = await agent.CreateSessionAsync() as ChatClientAgentSession;
+        await agent.RunStreamingAsync([new(ChatRole.User, "first")], session).ToListAsync();
+        await agent.RunStreamingAsync([new(ChatRole.User, "second")], session).ToListAsync();
+
+        // Assert - the second call should include chat history (first user message + first response) plus the new message
+        Assert.Equal(2, capturedMessages.Count);
+        var secondCallMessages = capturedMessages[1].ToList();
+        Assert.Equal(3, secondCallMessages.Count);
+        Assert.Equal("first", secondCallMessages[0].Text);
+        Assert.Equal("response", secondCallMessages[1].Text);
+        Assert.Equal("second", secondCallMessages[2].Text);
+    }
+
     /// <summary>
     /// Verify that RunStreamingAsync throws when a <see cref="ChatHistoryProvider"/> is provided and the chat client returns a conversation id.
     /// </summary>

dotnet/tests/Microsoft.Agents.AI.Workflows.UnitTests/JsonSerializationTests.cs

@@ -672,4 +672,104 @@ public class JsonSerializationTests
 
         ValidateCheckpoint(retrievedCheckpoint, prototype);
     }
+
+    /// <summary>
+    /// Verifies that the default behavior (without AllowOutOfOrderMetadataProperties) fails
+    /// when $type metadata is not the first property, demonstrating the PostgreSQL jsonb issue.
+    /// See: https://github.com/microsoft/agent-framework/issues/2962
+    /// </summary>
+    [Fact]
+    public void Test_OutOfOrderMetadataProperties_WithoutOption_Fails()
+    {
+        // Arrange
+        JsonMarshaller marshaller = new();
+        EdgeInfo edgeInfo = TestEdgeInfo_DirectNoCondition;
+
+        // Serialize to JSON
+        JsonElement serialized = marshaller.Marshal(edgeInfo);
+        string json = serialized.GetRawText();
+
+        // Simulate PostgreSQL jsonb behavior: reorder properties so $type is not first
+        string reorderedJson = ReorderJsonPropertiesToMoveTypeDiscriminatorLast(json);
+
+        // Act & Assert - Without the option, deserialization should fail
+        JsonElement reorderedElement = JsonDocument.Parse(reorderedJson).RootElement;
+        Action act = () => marshaller.Marshal<EdgeInfo>(reorderedElement);
+
+        act.Should().Throw<JsonException>();
+    }
+
+    /// <summary>
+    /// Simulates PostgreSQL jsonb behavior where property order is not preserved,
+    /// causing $type metadata to not be the first property.
+    /// This test verifies that deserialization works when AllowOutOfOrderMetadataProperties is enabled.
+    /// See: https://github.com/microsoft/agent-framework/issues/2962
+    /// </summary>
+    [Fact]
+    public void Test_OutOfOrderMetadataProperties_WithOptionEnabled_Succeeds()
+    {
+        // Arrange
+        EdgeInfo edgeInfo = TestEdgeInfo_DirectNoCondition;
+
+        // Serialize to JSON using standard marshaller
+        JsonMarshaller marshaller = new();
+        JsonElement serialized = marshaller.Marshal(edgeInfo);
+        string json = serialized.GetRawText();
+
+        // Simulate PostgreSQL jsonb behavior: reorder properties so $type is not first
+        string reorderedJson = ReorderJsonPropertiesToMoveTypeDiscriminatorLast(json);
+        JsonElement reorderedElement = JsonDocument.Parse(reorderedJson).RootElement;
+
+        // Act - Deserialize with AllowOutOfOrderMetadataProperties enabled via JsonSerializerOptions
+        JsonSerializerOptions options = new() { AllowOutOfOrderMetadataProperties = true };
+        JsonMarshaller marshallerWithOption = new(options);
+        EdgeInfo deserialized = marshallerWithOption.Marshal<EdgeInfo>(reorderedElement);
+
+        // Assert
+        deserialized.Should().Match(edgeInfo.CreatePolyValidator());
+    }
+
+    private static string ReorderJsonPropertiesToMoveTypeDiscriminatorLast(string json)
+    {
+        // Parse JSON, extract $type, rebuild with $type at end
+        using JsonDocument doc = JsonDocument.Parse(json);
+        JsonElement root = doc.RootElement;
+
+        Dictionary<string, JsonElement> properties = [];
+        JsonElement? typeValue = null;
+
+        foreach (JsonProperty prop in root.EnumerateObject())
+        {
+            if (prop.Name == "$type")
+            {
+                typeValue = prop.Value.Clone();
+            }
+            else
+            {
+                properties[prop.Name] = prop.Value.Clone();
+            }
+        }
+
+        // Rebuild JSON with $type last
+        using System.IO.MemoryStream ms = new();
+        using (Utf8JsonWriter writer = new(ms))
+        {
+            writer.WriteStartObject();
+            foreach (KeyValuePair<string, JsonElement> kvp in properties)
+            {
+                writer.WritePropertyName(kvp.Key);
+                kvp.Value.WriteTo(writer);
+            }
+
+            if (typeValue.HasValue)
+            {
+                writer.WritePropertyName("$type");
+                typeValue.Value.WriteTo(writer);
+            }
+
+            writer.WriteEndObject();
+        }
+
+        return System.Text.Encoding.UTF8.GetString(ms.ToArray());
+    }
 }