always return full message object if tool calls are in response

Author: leafo

README.md

@@ -349,16 +349,21 @@ Constructor for the ResponsesChatSession.
   - `tools`: Array of tool definitions
   - `previous_response_id`: Resume from a previous response
 
-##### `session:send(input, stream_callback)`
+##### `session:send(input, opts={})`
 
 Sends input and returns the response, maintaining conversation state
 automatically.
 
 - `input`: A string or array of message objects.
-- `stream_callback`: Optional function for streaming responses.
+- `opts`: (optional) A table of per-request overrides. For backward
+  compatibility, a function can be passed instead and will be treated as
+  `{stream_callback = fn}`.
+  - `stream_callback`: Optional function for streaming responses.
+  - Any other Responses API parameter (e.g. `tool_choice`, `model`) to
+    override the session default for this request.
 
-Returns a response object on success (or accumulated text string when
-streaming). On failure, returns `nil`, an error message, and the raw response.
+Returns a response object on success, or accumulated text when streaming. On
+failure, returns `nil`, an error message, and the raw response.
 
 Response objects have helper methods:
 - `response:get_output_text()`: Extract all text content as a string
@@ -385,8 +390,8 @@ Lower-level method to create a response with additional options.
 - `opts`: Additional options (model, temperature, tools, previous_response_id, etc.)
 - `stream_callback`: Optional function for streaming responses.
 
-Returns a response object on success. On failure, returns `nil`, an error
-message, and the raw response.
+Returns a response object on success, or accumulated text when streaming. On
+failure, returns `nil`, an error message, and the raw response.
 
 #### ChatSession
 
@@ -724,4 +729,3 @@ else
   error("Unknown function: " .. name)
 end
 ```
-

openai/chat_completions.lua

@@ -279,6 +279,9 @@ do
         if append_response then
           self:append_message(message)
         end
+        if message.tool_calls then
+          return message
+        end
         return message.content or message
       end
       local out, err = parse_chat_response(response)

openai/chat_completions.moon

@@ -294,6 +294,9 @@ class ChatSession
       if append_response
         @append_message message
 
+      if message.tool_calls
+        return message
+
       return message.content or message
 
     out, err = parse_chat_response response

spec/openai_spec.moon

@@ -688,6 +688,50 @@ describe "OpenAI API Client", ->
       -- Verify response is appended to chat history
       assert.same response, chat.messages[#chat.messages]
 
+    it "returns the full assistant message when streaming includes text and tool calls", ->
+      package.loaded["socket.http"] = {
+        request: (opts={}) ->
+          chunks = {
+            "data: {\"object\": \"chat.completion.chunk\", \"choices\": [{\"delta\": {\"content\": \"Let me check.\"}, \"index\": 0}]}\n"
+            "data: {\"object\": \"chat.completion.chunk\", \"choices\": [{\"delta\": {\"tool_calls\": [{\"index\": 0, \"id\": \"call_tool\", \"type\": \"function\", \"function\": {\"name\": \"lookup_weather\"}}]}, \"index\": 0}]}\n"
+            "data: {\"object\": \"chat.completion.chunk\", \"choices\": [{\"delta\": {\"tool_calls\": [{\"index\": 0, \"function\": {\"arguments\": \"{\\\"location\\\":\\\"Paris\\\"}\"}}]}, \"index\": 0}]}\n"
+            "data: [DONE]"
+          }
+          for chunk in *chunks
+            opts.sink chunk
+          true, 200, {}
+      }
+
+      client = OpenAI "test-api-key"
+      chat = client\new_chat_session {
+        tools: {
+          {
+            type: "function"
+            ["function"]: {
+              name: "lookup_weather"
+              parameters: {}
+            }
+          }
+        }
+      }
+
+      response = assert chat\send "What's the weather in Paris?", (chunk) -> nil
+
+      assert.same {
+        role: "assistant"
+        content: "Let me check."
+        tool_calls: {
+          {
+            id: "call_tool"
+            type: "function"
+            ["function"]: {
+              name: "lookup_weather"
+              arguments: "{\"location\":\"Paris\"}"
+            }
+          }
+        }
+      }, response
+
   describe "responses", ->
     it "creates a response (raw API)", ->
       client = OpenAI "test-api-key"