diff --git a/src/chatbox.tsx b/src/chatbox.tsx
index d57279c..6893630 100644
--- a/src/chatbox.tsx
+++ b/src/chatbox.tsx
@@ -15,6 +15,7 @@ import ChatGPT, {
   FetchResponse,
   Message as MessageType,
   MessageDetail,
+  ToolCall,
 } from "./chatgpt";
 import Message from "./message";
 import models from "./models";
@@ -71,12 +72,48 @@ export default function ChatBOX(props: {
     let responseTokenCount = 0;
     chatStore.streamMode = true;
     const allChunkMessage: string[] = [];
+    const allChunkTool: ToolCall[] = [];
     setShowGenerating(true);
     for await (const i of client.processStreamResponse(response)) {
       chatStore.responseModelName = i.model;
       responseTokenCount += 1;
       allChunkMessage.push(i.choices[0].delta.content ?? "");
-      setGeneratingMessage(allChunkMessage.join(""));
+      const tool_calls = i.choices[0].delta.tool_calls;
+      if (tool_calls) {
+        for (const tool_call of tool_calls) {
+          // init
+          if (tool_call.id) {
+            allChunkTool.push({
+              id: tool_call.id,
+              type: tool_call.type,
+              index: tool_call.index,
+              function: {
+                name: tool_call.function.name,
+                arguments: "",
+              },
+            });
+            continue;
+          }
+
+          // update tool call arguments
+          const tool = allChunkTool.find(
+            (tool) => tool.index === tool_call.index
+          );
+
+          if (!tool) {
+            console.log("tool (by index) not found", tool_call.index);
+            continue;
+          }
+
+          tool.function.arguments += tool_call.function.arguments;
+        }
+      }
+      setGeneratingMessage(
+        allChunkMessage.join("") +
+          allChunkTool.map((tool) => {
+            return `Tool Call ID: ${tool.id}\nType: ${tool.type}\nFunction: ${tool.function.name}\nArguments: ${tool.function.arguments}`;
+          })
+      );
     }
     setShowGenerating(false);
     const content = allChunkMessage.join("");
@@ -103,6 +140,7 @@ export default function ChatBOX(props: {
     chatStore.history.push({
       role: "assistant",
       content,
+      tool_calls: allChunkTool,
       hide: false,
       token: responseTokenCount,
       example: false,
diff --git a/src/chatgpt.ts b/src/chatgpt.ts
index 9affb8d..6704c46 100644
--- a/src/chatgpt.ts
+++ b/src/chatgpt.ts
@@ -8,17 +8,43 @@ export interface MessageDetail {
   text?: string;
   image_url?: ImageURL;
 }
+export interface ToolCall {
+  index: number;
+  id?: string;
+  type: string;
+  function: {
+    name: string;
+    arguments: string;
+  };
+}
 export interface Message {
   role: "system" | "user" | "assistant" | "tool";
   content: string | MessageDetail[];
   name?: "example_user" | "example_assistant";
-  tool_calls?: {
-    id: string;
-    type: string;
-    function: any;
-  }[];
+  tool_calls?: ToolCall[];
   tool_call_id?: string;
 }
+
+interface Delta {
+  role?: string;
+  content?: string;
+  tool_calls?: ToolCall[];
+}
+
+interface Choices {
+  index: number;
+  delta: Delta;
+  finish_reason: string | null;
+}
+
+export interface StreamingResponseChunk {
+  id: string;
+  object: string;
+  created: number;
+  model: string;
+  system_fingerprint: string;
+  choices: Choices[];
+}
 export const getMessageText = (message: Message): string => {
   if (typeof message.content === "string") {
     return message.content;
@@ -252,7 +278,7 @@ class Chat {
         console.log("line", line);
         try {
           const jsonStr = line.slice("data:".length).trim();
-          const json = JSON.parse(jsonStr);
+          const json = JSON.parse(jsonStr) as StreamingResponseChunk;
           yield json;
         } catch (e) {
           console.log(`Chunk parse error at: ${line}`);
diff --git a/src/message.tsx b/src/message.tsx
index b692b03..b7f8f1e 100644
--- a/src/message.tsx
+++ b/src/message.tsx
@@ -299,7 +299,8 @@ export default function Message(props: Props) {
                       <div className="bg-blue-300 dark:bg-blue-800 p-1 rounded">
                         <strong>Tool Call ID: {tool_call?.id}</strong>
                         <p>Type: {tool_call?.type}</p>
-                        <p>Function: {JSON.stringify(tool_call?.function)}</p>
+                        <p>Function: {tool_call.function.name}</p>
+                        <p>Arguments: {tool_call.function.arguments}</p>
                       </div>
                     </>
                   ))}