.NET: Merge AgentRunOptions.AdditionalProperties into ChatOptions.AdditionalProperties

dotnet/src/Microsoft.Agents.AI/ChatClient/ChatClientAgent.cs

@@ -519,16 +519,16 @@ await thread.AIContextProvider.InvokedAsync(new(inputMessages, aiContextProvider
     {
         ChatOptions? requestChatOptions = (runOptions as ChatClientAgentRunOptions)?.ChatOptions?.Clone();
 
-        // If no agent chat options were provided, return the request chat options as is.
+        // If no agent chat options were provided, return the request chat options with just agent run options overrides.
         if (this._agentOptions?.ChatOptions is null)
         {
-            return GetContinuationTokenAndApplyBackgroundResponsesProperties(requestChatOptions, runOptions);
+            return ApplyAgentRunOptionsOverrides(requestChatOptions, runOptions);
         }
 
-        // If no request chat options were provided, use the agent's chat options clone.
+        // If no request chat options were provided, use the agent's chat options clone with agent run options overrides.
         if (requestChatOptions is null)
         {
-            return GetContinuationTokenAndApplyBackgroundResponsesProperties(this._agentOptions?.ChatOptions.Clone(), runOptions);
+            return ApplyAgentRunOptionsOverrides(this._agentOptions?.ChatOptions.Clone(), runOptions);
         }
 
         // If both are present, we need to merge them.
@@ -557,9 +557,9 @@ await thread.AIContextProvider.InvokedAsync(new(inputMessages, aiContextProvider
         // Merge only the additional properties from the agent if they are not already set in the request options.
         if (requestChatOptions.AdditionalProperties is not null && this._agentOptions.ChatOptions.AdditionalProperties is not null)
         {
-            foreach (var propertyKey in this._agentOptions.ChatOptions.AdditionalProperties.Keys)
+            foreach (var kvp in this._agentOptions.ChatOptions.AdditionalProperties)
             {
-                _ = requestChatOptions.AdditionalProperties.TryAdd(propertyKey, this._agentOptions.ChatOptions.AdditionalProperties[propertyKey]);
+                _ = requestChatOptions.AdditionalProperties.TryAdd(kvp.Key, kvp.Value);
             }
         }
         else
@@ -624,9 +624,9 @@ await thread.AIContextProvider.InvokedAsync(new(inputMessages, aiContextProvider
             }
         }
 
-        return GetContinuationTokenAndApplyBackgroundResponsesProperties(requestChatOptions, runOptions);
+        return ApplyAgentRunOptionsOverrides(requestChatOptions, runOptions);
 
-        static (ChatOptions?, ChatClientAgentContinuationToken?) GetContinuationTokenAndApplyBackgroundResponsesProperties(ChatOptions? chatOptions, AgentRunOptions? agentRunOptions)
+        static (ChatOptions?, ChatClientAgentContinuationToken?) ApplyAgentRunOptionsOverrides(ChatOptions? chatOptions, AgentRunOptions? agentRunOptions)
         {
             if (agentRunOptions?.AllowBackgroundResponses is not null)
             {
@@ -643,6 +643,17 @@ await thread.AIContextProvider.InvokedAsync(new(inputMessages, aiContextProvider
                 chatOptions.ContinuationToken = agentContinuationToken!.InnerToken;
             }
 
+            // Add/Replace any additional properties from the AgentRunOptions, since they should always take precedence.
+            if (agentRunOptions?.AdditionalProperties is { Count: > 0 })
+            {
+                chatOptions ??= new ChatOptions();
+                chatOptions.AdditionalProperties ??= new();
+                foreach (var kvp in agentRunOptions.AdditionalProperties)
+                {
+                    chatOptions.AdditionalProperties[kvp.Key] = kvp.Value;
+                }
+            }
+
             return (chatOptions, agentContinuationToken);
         }
     }