update

src/utils.jl

@@ -221,6 +221,8 @@ function formatMsgForLLM(ctx::agentContext, agentEventSink)::Dict{String, Any}
   for msg in ctx.messages
     if msg isa userMessage
       push!(messages, _userMessageToOpenAI(msg))
+    elseif msg isa assistantMessageToolCall
+      push!(messages, _assistantMessageToolCallToOpenAI(msg))
     elseif msg isa assistantMessage
       push!(messages, _assistantMessageToOpenAI(msg))
     elseif msg isa toolResultMessage
@@ -336,6 +338,44 @@ end
 
 
 """
+Convert an assistantMessageToolCall to OpenAI message format.
+
+Produces a message with role="assistant", content=null, and a tool_calls array:
+{
+  "role": "assistant",
+  "content": null,
+  "tool_calls": [
+    {
+      "id": "call_1",
+      "type": "function",
+      "function": {
+        "name": "get_weather",
+        "arguments": "{\"location\": \"San Francisco, CA\"}"
+      }
+    }
+  ]
+}
+"""
+function _assistantMessageToolCallToOpenAI(msg::assistantMessageToolCall)::Dict{String, Any}
+  tool_calls = Dict{String, Any}[]
+  for tc in msg.toolCalls
+    push!(tool_calls, Dict(
+      "id" => tc.id,
+      "type" => tc.type,
+      "function" => Dict(
+        "name" => tc.name,
+        "arguments" => JSON.json(tc.arguments)
+      )
+    ))
+  end
+  return Dict(
+    "role" => "assistant",
+    "content" => nothing,
+    "tool_calls" => tool_calls
+  )
+end
+
+"""
 Convert an assistantMessage to OpenAI message format.
 """
 function _assistantMessageToOpenAI(msg::assistantMessage)::Dict{String, Any}