Access to Tool Call in Chat History

[RandyPatterson]

in .NET I'm trying to get access to the Tool Call History for a conversation. I would expect to find the message with a role of "Tool" in the response. but the response returned from IChatCompletionService.GetChatMessageContentAsync() does not contain any 'tool' role messages. Also, the ToolCalls collection property is always empty. SK is definetly making several tool calls before arriving at the correct answer. Is this a bug or am I missing something?

Using AzureOpenAI GPT-4o model.

[sophialagerkranspandey]

Tagging @SergeyMenshykh

[shyamnamboodiripad]

I see that the tool messages (both tool calls and tool call results) are being added to the ChatHistory that is supplied to GetChatMessageContentAsync. However, as @RandyPatterson mentioned above, the returned ChatMessageContent does not contain any info about the tools used. (In case this matters, I specified FunctionChoiceBehavior.Auto() as part of my PromptExecutionSettings.)

I also find this behavior a little odd since the ChatHistory is being mutated to include the intermediate tool calls and tool call results, but not the final response. Intuitively, I would have expected the value returned from GetChatMessageContent to include the tool related messages in addition to the final response and I would have expected ChatHistory to remain unaltered. However, considering that the returned object is a ChatMessageContent, I am guessing it is not possible to model the tool call messages, tool call result messages, and the final response message as part of the same returned object (since some of these messages can have a different role)?

The above semantics are also different from how tool calls are modeled in the Microsoft.Extensions.AI abstractions for .NET. Microsoft.Extensions.AI's IChatClient.GetResponseAsync() returns a ChatResponse which includes individual ChatMessages for tool calls, tool call results as well as the final response (each of which can specify their own independent ChatRoles).