Trello agent

agent.js

// ✅ STEP 1: Environment Setup
// Make sure you have a .env file in your project root with this line:
//
// OPENAI_API_KEY=sk-your-openai-api-key
//
// Do NOT hardcode your API key in this file. Use dotenv to load it securely.

import { ChatOpenAI } from "@langchain/openai";
import { createReactAgent } from "@langchain/langgraph/prebuilt";
import { HumanMessage, AIMessage } from "@langchain/core/messages";
import dotenv from "dotenv";
import * as readline from "node:readline/promises";
import { stdin as input, stdout as output } from "node:process";
import { MultiServerMCPClient } from "@langchain/mcp-adapters";

// Load variables from .env file
dotenv.config();

// ✅ STEP 2: Add your Trello MCP URL
// Go to https://mcp.composio.dev, connect Trello, click "Cursor", and copy your tool URL.
// Replace the placeholder below with your actual Trello tool URL.
const mcpServers = {
  trello: {
    transport: "sse",
    url: "https://mcp.composio.dev/trello/YOUR-TRELLO-ID"
  }
};

async function runChat() {
  const rl = readline.createInterface({ input, output });
  const chatHistory = [];

  // Initialize MCP client and load tools
  const client = new MultiServerMCPClient(mcpServers);
  const tools = await client.getTools();

  // ✅ STEP 3: Load GPT-4o via OpenAI
  const model = new ChatOpenAI({
    modelName: "gpt-4o",
    temperature: 0,
    openAIApiKey: process.env.OPENAI_API_KEY
  });

  // Create the LangChain agent using the tools
  const agent = createReactAgent({ llm: model, tools });

  console.log("Agent is ready. Type your message or 'exit' to quit.\n");

  // 🔄 Main chat loop
  while (true) {
    const userInput = await rl.question("You: ");
    if (!userInput.trim()) continue;
    if (userInput.toLowerCase() === "exit") break;

    chatHistory.push(new HumanMessage(userInput));
    console.log("\nAgent thinking...\n");

    try {
      const result = await agent.invoke({ messages: chatHistory });
      const lastMsg = result.messages[result.messages.length - 1];
      const reply = typeof lastMsg.content === "string"
        ? lastMsg.content
        : JSON.stringify(lastMsg.content);

      console.log("Agent:", reply, "\n");
      chatHistory.push(new AIMessage(reply));
    } catch (err) {
      console.error("Agent error:", err.message);
    }
  }

  rl.close();
  if (client?.close) await client.close();
  console.log("Chat ended.");
}

runChat();