🧩 Dynamic Travel Planner with LangChain + Dappier MCP using `mcp-use`

This cookbook demonstrates how to build a real-time, AI-powered travel planner using LangChain, Dappier MCP, and the lightweight **mcp-use** client. By integrating live data through the Model Context Protocol (MCP), this guide walks through how to create structured, tool-augmented agents without using the OpenAI Agents SDK. In this cookbook, you’ll explore:

LangChain + OpenAI: A modular framework to build LLM-powered applications with support for agents, tools, and memory.
Dappier MCP: A Model Context Protocol server that connects your agents to real-time, rights-cleared, AI-powered tools such as live search, weather, stock data, and content recommendations.
mcp-use: A lightweight Python client that bridges any LLM with any MCP server using standard transports like stdio and http—without relying on proprietary SDKs.
Dynamic Travel Planning: A real-world use case where the assistant creates a multi-day itinerary using live weather, events, and hotel data sourced via MCP.

This example demonstrates a flexible architecture for building real-time, tool-augmented assistants and lays the foundation for other real-world applications powered by dynamic context, tool use, and AI reasoning.

📦 Installation

To get started, install the required tools and dependencies:

Step 1: Install uv (required to run the Dappier MCP server) macOS / Linux:

curl -LsSf https://astral.sh/uv/install.sh | sh

Windows:

powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"

Step 2: Create a Virtual Environment (Recommended) Create and activate a virtual environment to isolate dependencies. macOS / Linux:

python3 -m venv venv
source venv/bin/activate

Windows:

python -m venv venv
venv\Scripts\activate

Step 3: Install Python Packages Install the necessary Python dependencies including LangChain and mcp-use.

pip install langchain-openai mcp-use python-dotenv

🔑 Setting Up API Keys

You’ll need API keys for both Dappier and OpenAI to authenticate your requests and access tools.

Dappier API Key Visit Dappier to generate your API key. Dappier provides free credits to help you get started. You can set the API key as an environment variable in your terminal:

export DAPPIER_API_KEY=your-dappier-api-key

Or include it in a .env file at the root of your project:

DAPPIER_API_KEY=your-dappier-api-key

OpenAI API Key Go to OpenAI to retrieve your API key. Set it in your terminal:

export OPENAI_API_KEY=your-openai-api-key

Or include it in your .env file:

OPENAI_API_KEY=your-openai-api-key

In your Python script, load the .env file:

Python

from dotenv import load_dotenv

load_dotenv()

⚙️ Import Dependencies

Start by importing the required modules to build the travel planner agent. This includes components from mcp-use, LangChain, and environment configuration.

Python

import asyncio
import os
from dotenv import load_dotenv
from langchain_openai import ChatOpenAI
from mcp_use import MCPAgent, MCPClient

These imports enable:

Loading API keys from the environment using dotenv
Running asynchronous workflows with asyncio
Accessing OpenAI models via LangChain
Connecting to the Dappier MCP server and executing tool-augmented queries using mcp-use

📝 Define User Input

We’ll collect basic trip preferences from the user: city, number of days, and travel start date.

Python

def get_user_input():
    city = input("Enter the city for your travel: ").strip()
    num_days = input("Enter the number of days for the trip: ").strip()
    travel_date = input("Enter the start date of travel (YYYY-MM-DD): ").strip()
    return city, num_days, travel_date

🛰️ Run the Agent with Dappier MCP

This function sets up the MCP agent using mcp-use, formulates the travel planning query, and executes it using real-time tools provided by the Dappier MCP server.

Python

async def run_travel_planner(city: str, num_days: str, travel_date: str):
    # Load environment variables
    load_dotenv()

    # Retrieve API key
    api_key = os.getenv("DAPPIER_API_KEY")
    if not api_key:
        raise ValueError("DAPPIER_API_KEY is not set")

    # MCPClient configuration using stdio transport (via uvx dappier-mcp)
    config = {
        "mcpServers": {
            "dappier": {
                "command": "uvx",
                "args": ["dappier-mcp"],
                "env": {
                    "DAPPIER_API_KEY": api_key
                }
            }
        }
    }

    # Create MCP client and LLM
    client = MCPClient.from_dict(config)
    llm = ChatOpenAI(model="gpt-4o")

    # Create the agent
    agent = MCPAgent(llm=llm, client=client, max_steps=30)

    try:
        # Formulate query
        query = f"""
        Generate a {num_days}-day travel itinerary for {city}, tailored to the real-time weather forecast for the selected date: {travel_date}. Follow these steps:

        Determine Current Date and Travel Period:
        Use Dappier's real-time search to identify the current date and calculate the trip duration based on user input.

        Fetch Weather Data:
        Retrieve the weather forecast for {city} during the selected dates to understand the conditions for each day.

        Fetch Live Events Data:
        Use Dappier's real-time search to find live events happening in {city} during the trip dates.

        Fetch Hotel Deals Data:
        Use Dappier's real-time search to find the best hotel deals with booking links in {city} during the trip dates.

        Design the Itinerary:
        Use the weather insights, live events, hotel deals to plan activities and destinations that suit the expected conditions.

        Output:
        Present a detailed {num_days}-day itinerary, including timing, activities, booking links, weather information for each day and travel considerations.
        """

        print("\n" + "-" * 40)
        print(f"Running itinerary generation for {city} starting {travel_date} for {num_days} days")
        print("\n=== Response ===\n")

        result = await agent.run(query, max_steps=30, Verbose=True)
        print(result)

    finally:
        # Clean up sessions
        if client.sessions:
            await client.close_all_sessions()

🚦 Initialize and Launch the Workflow

The main() function collects user input, then launches the asynchronous workflow to run the travel planner using mcp-use and Dappier MCP.

Python

async def main():
    city, num_days, travel_date = get_user_input()
    await run_travel_planner(city, num_days, travel_date)

To start the planner, run the main function using asyncio:

Python

if __name__ == "__main__":
    asyncio.run(main())

Enter the city for your travel: london
Enter the number of days for the trip: 5
Enter the start date of travel: today  

----------------------------------------
Running itinerary generation for london starting today for 5 days

=== Response ===

[04/23/25 13:16:16] INFO     Processing request of type ListToolsRequest                                                                        server.py:534
                    INFO     Processing request of type ListToolsRequest                                                                        server.py:534
[04/23/25 13:16:22] INFO     Processing request of type CallToolRequest                                                                         server.py:534
[04/23/25 13:16:25] INFO     HTTP Request: POST https://api.dappier.com/app/aimodel/am_01j06ytn18ejftedz6dyhz2b15 "HTTP/1.1 200 OK"           _client.py:1025
[04/23/25 13:16:29] INFO     Processing request of type CallToolRequest                                                                         server.py:534
[04/23/25 13:16:37] INFO     HTTP Request: POST https://api.dappier.com/app/aimodel/am_01j06ytn18ejftedz6dyhz2b15 "HTTP/1.1 200 OK"           _client.py:1025
                    INFO     Processing request of type CallToolRequest                                                                         server.py:534
[04/23/25 13:16:45] INFO     HTTP Request: POST https://api.dappier.com/app/aimodel/am_01j06ytn18ejftedz6dyhz2b15 "HTTP/1.1 200 OK"           _client.py:1025
                    INFO     Processing request of type CallToolRequest                                                                         server.py:534
[04/23/25 13:16:51] INFO     HTTP Request: POST https://api.dappier.com/app/aimodel/am_01j06ytn18ejftedz6dyhz2b15 "HTTP/1.1 200 OK"           _client.py:1025
Here's a detailed 5-day travel itinerary for your trip to London, tailored to the real-time weather forecast and live events from April 23 to April 27, 2025. 🌟

---

### Day 1: April 23, 2025 (Wednesday)
- **Weather**: Cloudy with rain, especially in the morning. High 55°F (13°C) / Low 47°F (8°C).
- **Suggested Activities**:
  - **St George's Day Celebrations**: Enjoy various events including Morris dancing and whisky tasting across the city. 🇬🇧
  - **The Queen of the Night Show**: Attend this tribute to Whitney Houston. 🎤
  - **Hotel**: Check into the Strand Palace for comfort and convenience.

### Day 2: April 24, 2025 (Thursday)
- **Weather**: Overcast with possible sprinkles. High 62°F (17°C) / Low 45°F (7°C).
- **Suggested Activities**:
  - Explore local venues for various concerts and live music. 🎶
  - **Shopping**: Visit Covent Garden and enjoy the nearby Resident Covent Garden Hotel for style and comfort.

### Day 3: April 25, 2025 (Friday)
- **Weather**: Mainly cloudy. High 64°F (18°C) / Low 42°F (6°C).
- **Suggested Activities**:
  - **Theatre Shows**: Catch a classic or modern production on the West End. 🎭
  - **Hotel**: Consider staying at the Royal National Hotel for a budget-friendly option.

### Day 4: April 26, 2025 (Saturday)
- **Weather**: Drizzly skies. High 62°F (17°C) / Low 49°F (9°C).
- **Suggested Activities**:
  - **Vivaldi by Candlelight**: Attend a stunning classical music experience. 🎻
  - **Explore Local Live Music**: Visit nearby gigs for a night out.
  - **Hotel**: Book the Corbigoe Hotel with prices starting at $64/night.

### Day 5: April 27, 2025 (Sunday)
- **Weather**: Mostly cloudy, chance of light rain. High 60°F (16°C) / Low 48°F (9°C).
- **Suggested Activities**:
  - **London Marathon**: Watch or even participate in this iconic event. 🏃‍♀️🏃‍♂️
  - **Theatre and Concerts**: End your trip with a flourish by catching another live performance.
  - **Hotel**: Relax at St Athans Hotel, known for its cozy setting.

---

**Travel Considerations:**
- **Hotel Booking**: Most hotels offer flexible options—consider locking in deals on Orbitz for exclusive offers and cancellation policies.
- **Packing**: Bring a light jacket, umbrella, and comfortable shoes for exploring the city.

Enjoy your spectacular 5-day trip to London filled with culture, entertainment, and cozy accommodations! 🌆✨

🌟 Highlights

This cookbook has guided you through building a dynamic travel planner using LangChain, Dappier MCP, and the **mcp-use** Python client. By connecting your agent to real-time tools via MCP, you’ve created an assistant capable of generating up-to-date travel itineraries based on live weather, events, and hotel deals. Key components of this workflow include:

LangChain + OpenAI: A modular framework for creating LLM-powered applications with agent capabilities.
Dappier MCP: A Model Context Protocol server that enables access to live, rights-cleared data through AI tools like real-time search, weather, and finance.
mcp-use: A lightweight open-source client to connect any LLM to any MCP server using stdio or http transports, without vendor lock-in.

This architecture can be extended to other real-time applications requiring dynamic data, tool use, and intelligent orchestration powered by the MCP ecosystem.

​📦 Installation

​🔑 Setting Up API Keys

​⚙️ Import Dependencies

​📝 Define User Input

​🛰️ Run the Agent with Dappier MCP

​🚦 Initialize and Launch the Workflow

​🌟 Highlights

📦 Installation

🔑 Setting Up API Keys

⚙️ Import Dependencies

📝 Define User Input

🛰️ Run the Agent with Dappier MCP

🚦 Initialize and Launch the Workflow

🌟 Highlights