From 844236da95042fa1d20fefccfbc9a1bcd5a70d6d Mon Sep 17 00:00:00 2001
From: Christian Bromann <git@bromann.dev>
Date: Wed, 15 Oct 2025 14:47:38 +0200
Subject: [PATCH] fix(integration): fix OpenAI custom tools example in JS

---
 .../javascript/integrations/chat/openai.mdx   | 22 +++++++++++--------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/oss/javascript/integrations/chat/openai.mdx b/src/oss/javascript/integrations/chat/openai.mdx
index 6472e2022..913e0f619 100644
--- a/src/oss/javascript/integrations/chat/openai.mdx
+++ b/src/oss/javascript/integrations/chat/openai.mdx
@@ -292,10 +292,10 @@ If you use a model that supports custom tools, you can use the `ChatOpenAI` clas
 
 ```typescript
 import { ChatOpenAI, customTool } from "@langchain/openai";
-import { createAgent } from "@langchain/classic";
+import { createAgent, HumanMessage } from "langchain";
 
 const codeTool = customTool(
-  async (input) => {
+  async () => {
     // ... Add code to execute the input
     return "Code executed successfully";
   },
@@ -309,11 +309,13 @@ const codeTool = customTool(
 const model = new ChatOpenAI({ model: "gpt-5" });
 
 const agent = createAgent({
-  llm: model,
+  model,
   tools: [codeTool],
 });
 
-const result = await agent.invoke("Use the tool to calculate 3^3");
+const result = await agent.invoke({
+  messages: [new HumanMessage("Use the tool to execute the code")],
+});
 console.log(result);
 ```
 
@@ -324,7 +326,7 @@ OpenAI supports the specification of a [context-free grammar](https://platform.o
 
 ```typescript
 import { ChatOpenAI, customTool } from "@langchain/openai";
-import { createAgent } from "@langchain/classic";
+import { createAgent, HumanMessage } from "langchain";
 
 const MATH_GRAMMAR = `
 start: expr
@@ -340,25 +342,27 @@ MUL: \"*\"
 `;
 
 const doMath = customTool(
-  async (input) => {
+  async () => {
     // ... Add code to parse and execute the input
     return "27";
   },
   {
     name: "do_math",
     description: "Evaluate a math expression",
-    format: { type: "grammar", grammar: MATH_GRAMMAR },
+    format: { type: "grammar", definition: MATH_GRAMMAR, syntax: "lark" },
   }
 );
 
 const model = new ChatOpenAI({ model: "gpt-5" });
 
 const agent = createAgent({
-  llm: model,
+  model,
   tools: [doMath],
 });
 
-const result = await agent.invoke("Use the tool to calculate 3^3");
+const result = await agent.invoke({
+  messages: [new HumanMessage("Use the tool to calculate 3^3")],
+});
 console.log(result);
 ```