diff --git a/endpoints/OAI/utils/chat_completion.py b/endpoints/OAI/utils/chat_completion.py
index a646924..9393e90 100644
--- a/endpoints/OAI/utils/chat_completion.py
+++ b/endpoints/OAI/utils/chat_completion.py
@@ -30,7 +30,7 @@ from endpoints.OAI.types.chat_completion import (
 )
 from endpoints.OAI.types.common import UsageStats
 from endpoints.OAI.utils.completion import _stream_collector
-from endpoints.OAI.types.tools import ToolCall
+from endpoints.OAI.utils.tools import ToolCallProcessor
 
 
 def _create_response(
@@ -49,7 +49,7 @@ def _create_response(
 
         tool_calls = generation["tool_calls"]
         if tool_calls:
-            message.tool_calls = postprocess_tool_call(tool_calls)
+            message.tool_calls = ToolCallProcessor.from_json(tool_calls)
 
         logprob_response = None
 
@@ -74,9 +74,14 @@ def _create_response(
 
             logprob_response = ChatCompletionLogprobs(content=collected_token_probs)
 
+        # Finish reason will always be present in a completion
+        # If a tool call is present, mark the finish reason as such
+        if message.tool_calls:
+            finish_reason = "tool_calls"
+
         choice = ChatCompletionRespChoice(
             index=index,
-            finish_reason=generation.get("finish_reason"),
+            finish_reason=finish_reason,
             stop_str=generation.get("stop_str"),
             message=message,
             logprobs=logprob_response,
@@ -120,18 +125,19 @@ def _create_stream_chunk(
             total_tokens=prompt_tokens + completion_tokens,
         )
     elif "finish_reason" in generation:
-        choice = ChatCompletionStreamChoice(
-            index=index,
-            finish_reason=generation.get("finish_reason"),
-        )
+        # Get the finish reason from the generation
+        finish_reason = generation.get("finish_reason")
+        choice = ChatCompletionStreamChoice(index=index, finish_reason=finish_reason)
 
         # lets check if we have tool calls since we are at the end of the generation
+        # Mark finish_reason as tool_calls since this is the last chunk
         if "tool_calls" in generation:
             tool_calls = generation["tool_calls"]
             message = ChatCompletionMessage(
-                tool_calls=postprocess_tool_call(tool_calls)
+                tool_calls=ToolCallProcessor.from_json(tool_calls)
             )
             choice.delta = message
+            choice.finish_reason = "tool_calls"
 
         choices.append(choice)
 
@@ -224,7 +230,7 @@ async def format_messages_with_template(
             message.content = concatenated_content
 
         if message.tool_calls:
-            message.tool_calls_json = json.dumps(message.tool_calls, indent=2)
+            message.tool_calls_json = ToolCallProcessor.to_json(message.tool_calls)
 
     special_tokens_dict = model.container.get_special_tokens(
         add_bos_token, ban_eos_token
@@ -482,12 +488,3 @@ async def generate_tool_calls(
         generations[gen_idx]["tool_calls"] = tool_calls[outer_idx]["text"]
 
     return generations
-
-
-def postprocess_tool_call(call_str: str) -> List[ToolCall]:
-    tool_calls = json.loads(call_str)
-    for tool_call in tool_calls:
-        tool_call["function"]["arguments"] = json.dumps(
-            tool_call["function"]["arguments"]
-        )
-    return [ToolCall(**tool_call) for tool_call in tool_calls]