Python MCP Line

What is Python MCP Line about?

Python MCP Line implements a Model Context Protocol server in Python to bridge LINE Bot messages with LLMs. It captures webhook events from LINE, stores messages in JSON, and offers standardized API endpoints for resource listing and reading.

How to use Python MCP Line?

1. Clone the repository and install dependencies via pip install -r requirements.txt.
2. Create a .env file with your LINE credentials and server settings.
3. Run the server with python src/line/server.py (or via the provided Dockerfile).
4. Configure your LLM client (e.g., Claude Desktop) to point to the MCP server using the line server entry.

Key features of Python MCP Line

• Asynchronous FastAPI server with full async support.
• Environment‑based configuration using python-dotenv.
• Automatic validation of LINE webhook signatures.
• Stores messages in data/messages.json for persistence.
• Pydantic models ensure request/response validation.
• Supports text, sticker, and image message types.
• Provides resource listing (line://<type>/data) and reading with optional filters (date, user, content).
• Comprehensive logging and error handling.

Use cases of Python MCP Line

• Enable LLMs to analyze real‑time or historic LINE conversations for sentiment analysis or content summarization.
• Build AI assistants that can reference past chat context from LINE.
• Archive LINE group chats for compliance or research purposes while keeping them accessible via a standard protocol.
• Integrate LINE messaging data into downstream analytics pipelines.

FAQ from the Python MCP Line

Q: Which Python version is required? A: Python 3.8 or newer.

Q: How are messages stored? A: In a JSON file (data/messages.json) by default, configurable via the MESSAGES_FILE env variable.

Q: Can I run the server in Docker? A: Yes, a Dockerfile is provided; build with docker build -t python-mcp-line . and run exposing the configured port.

Q: What environment variables are needed? A: LINE_CHANNEL_SECRET, LINE_ACCESS_TOKEN, SERVER_PORT, and MESSAGES_FILE.

Q: How do I add the server to Claude Desktop? A: Add a mcpServers entry under line with the command and env variables as shown in the README.

Python LINE MCP Server

A Model Context Protocol server implementation in Python that provides access to LINE Bot messages. This server enables Language Models to read and analyze LINE conversations through a standardized interface.

Features

Core Functionality

• Asynchronous operation using Python's asyncio
• Environment-based configuration using python-dotenv
• Comprehensive logging system
• LINE Bot webhook event handling
• Message storage in JSON format
• FastAPI integration for API endpoints
• Pydantic models for data validation
• Support for text, sticker, and image messages

Prerequisites

• Python 3.8+
• Required Python packages:
  • fastapi
  • pydantic
  • python-dotenv
  • mcp-server
  • line-bot-sdk
  • uvicorn

Installation

git clone https://github.com/amornpan/py-mcp-line.git
cd py-mcp-line
pip install -r requirements.txt

Project Structure

PY-MCP-LINE/
├── src/
│   └── line/
│       ├── __init__.py
│       └── server.py
├── data/
│   └── messages.json
├── tests/
│   ├── __init__.py
│   └── test_line.py
├── .env
├── .env.example
├── .gitignore
├── README.md
├── Dockerfile
└── requirements.txt

Directory Structure Explanation

• src/line/ - Main source code directory
  • __init__.py - Package initialization
  • server.py - Main server implementation
• data/ - Data storage directory
  • messages.json - Stored LINE messages
• tests/ - Test files directory
  • __init__.py - Test package initialization
  • test_line.py - LINE functionality tests
• .env - Environment configuration file (not in git)
• .env.example - Example environment configuration
• .gitignore - Git ignore rules
• README.md - Project documentation
• Dockerfile - Docker configuration
• requirements.txt - Project dependencies

Configuration

Create a .env file in the project root:

LINE_CHANNEL_SECRET=your_channel_secret
LINE_ACCESS_TOKEN=your_access_token
SERVER_PORT=8000
MESSAGES_FILE=data/messages.json

API Implementation Details

Resource Listing

@app.list_resources()
async def list_resources() -> list[Resource]

• Lists available message types from the LINE Bot
• Returns resources with URIs in the format line://<message_type>/data
• Includes resource descriptions and MIME types

Resource Reading

@app.read_resource()
async def read_resource(uri: AnyUrl) -> str

• Reads messages of the specified type
• Accepts URIs in the format line://<message_type>/data
• Returns messages in JSON format
• Supports filtering by date, user, or content

Usage with Claude Desktop

Add to your Claude Desktop configuration:

On MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json On Windows: %APPDATA%/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "line": {
      "command": "python",
      "args": [
        "server.py"
      ],
      "env": {
        "LINE_CHANNEL_SECRET": "your_channel_secret",
        "LINE_ACCESS_TOKEN": "your_access_token",
        "SERVER_PORT": "8000",
        "MESSAGES_FILE": "data/messages.json"
      }
    }
  }
}

Error Handling

The server implements comprehensive error handling for:

• Webhook validation failures
• Message storage errors
• Resource access errors
• URI validation
• LINE API response errors

All errors are logged and returned with appropriate error messages.

Security Features

• Environment variable based configuration
• LINE message signature validation
• Proper error handling
• Input validation through Pydantic

Contact Information

Amornpan Phornchaicharoen

Feel free to reach out to me if you have any questions about this project or would like to collaborate!

---

Made with ❤️ by Amornpan Phornchaicharoen

Author

Amornpan Phornchaicharoen

Requirements

Create a requirements.txt file with:

fastapi>=0.104.1
pydantic>=2.10.6
uvicorn>=0.34.0 
python-dotenv>=1.0.1
line-bot-sdk>=3.5.0
anyio>=4.5.0
mcp==1.2.0

These versions have been tested and verified to work together. The key components are:

• fastapi and uvicorn for the API server
• pydantic for data validation
• line-bot-sdk for LINE Bot integration
• mcp for Model Context Protocol implementation
• python-dotenv for environment configuration
• anyio for asynchronous I/O support

Acknowledgments

• LINE Developers for the LINE Messaging API
• Model Context Protocol community
• Python FastAPI community
• Contributors to the python-dotenv project