update

src/type.jl

@@ -144,7 +144,7 @@ assistantMessage("assistant", [textContent("Hello!")], "", "", "gpt-4", ..., "en
 ```
 """
 function assistantMessage(; role="assistant", content=Vector{messageContent}(),
-    api="", provider="", model="", usage=llmUsage(0, 0), stopReason="end_turn",
+    api="", provider="", model=nothing, usage=llmUsage(0, 0), stopReason="end_turn",
     errorMessage=nothing, timestamp=now())
     return assistantMessage(role, content, api, provider, model, usage, stopReason, errorMessage, timestamp)
 end
@@ -309,7 +309,7 @@ end
 
 mutable struct agentState                     # Mutable runtime state of an agent
     systemPrompt::String                      # System prompt for the agent
-    model::llmModel                           # LLM model to use
+    model::Union{llmModel, Nothing}                           # LLM model to use
     tools::OrderedDict{String, agentTool}     # Available tools keyed by name, insertion-ordered
 
     # messages history includes userMessage, assistantMessage, toolResultMessage. NO system prompt
@@ -341,21 +341,21 @@ julia> state = agentState(systemPrompt="You are a helpful assistant")
 agentState("You are a helpful assistant", OrderedDict{String, agentTool}(), agentMessage[], String[], nothing)
 """
 function agentState(
-    systemPrompt::String="",
-    model::llmModel=llmModel{String}("", "", "unknown", "unknown", "", false, String[], 
-                                    modelCost(0.0, 0.0, 0.0, 0.0), 0, 0),
-    tools::OrderedDict{String, agentTool}=OrderedDict{String, agentTool}(),
-    messages::Vector{agentMessage}=agentMessage[],
+  systemPrompt::String="",
+  model::llmModel=llmModel{String}("", "unknown", "unknown", "", false, String[], 
+                                  modelCost(0.0, 0.0, 0.0, 0.0), 0, 0),
+  tools::OrderedDict{String, agentTool}=OrderedDict{String, agentTool}(),
+  messages::Vector{agentMessage}=agentMessage[],
 )
-    agentState(
-      systemPrompt,
-      model,
-      deepcopy(tools),
-      deepcopy(messages),
-      Vector{String}(),
-      false,
-      nothing,
-    )
+  agentState(
+    systemPrompt,
+    model,
+    deepcopy(tools),
+    deepcopy(messages),
+    Vector{String}(),
+    false,
+    nothing,
+  )
 end