The Model Context Protocol (MCP): A Straightforward Guide for Developers in 2025


If you’re a developer or tech enthusiast wondering what MCP is or how you can actually use it, this post is for you. Let’s demystify the Model Context Protocol (MCP) in the most straightforward way possible, and show you how to get started right now.

TL;DR: MCP is like an open standard API layer for AI agents to read, write, and work with your data and tools in a consistent way—no more custom connectors for every tool.


What is MCP?

MCP (Model Context Protocol) is an open standard and open-source framework announced by Anthropic in November 2024. Its goal is simple:

Standardize how AI systems (like LLMs) connect to external tools and data sources.

Instead of writing custom integrations for every data source (think the classic N×M problem), MCP defines a universal interface for:

  • Reading files
  • Executing functions
  • Handling context-rich prompts

It’s like OpenAPI for AI assistants.


Why Does MCP Matter?

Before MCP, developers had to deal with:

  • Custom plugins (e.g., ChatGPT’s 2023 plugin framework)
  • Proprietary function-calling APIs
  • Vendor-specific connectors

These approaches worked, but they didn’t interoperate. MCP fixes this by:

✅ Defining a single protocol over JSON-RPC 2.0
✅ Reusing message patterns from Language Server Protocol (LSP)
✅ Supporting secure, bidirectional connections

This standardization has led major AI providers—including OpenAI and Google DeepMind—to adopt MCP in 2025.


How Does MCP Work?

At its simplest, MCP has two roles:

1️⃣ MCP Server

  • Exposes your data or functionality
  • Think of it like an API that the AI can call

2️⃣ MCP Client

  • The AI-powered tool or assistant
  • Connects to the server, issues commands, and reads data

Example: A Claude or ChatGPT desktop app can run an MCP client to read your local files via an MCP server on your machine.


Core Features

  • Standardized message format over JSON-RPC 2.0
  • SDKs in Python, TypeScript, C#, Java
  • Secure permissioning (but be aware of injection attacks)
  • Contextual metadata tagging
  • Works with local and cloud servers

Real-World Examples

🖥️ Desktop assistants
Claude Desktop runs an MCP server locally so it can access your files securely.

🏢 Enterprise assistants
Block integrated MCP to connect AI assistants with internal CRM systems.

💻 IDEs and coding tools

  • Replit
  • Sourcegraph
  • Zed

These use MCP to let AI coding assistants read and write project files in real time.


Getting Started with MCP

Setting Up Your First MCP Server

Here’s a simple Python example to get you started:

from mcp import MCPServer
import asyncio

# Create a simple MCP server
server = MCPServer("my-first-server")

@server.tool("get_current_time")
async def get_time():
    """Returns the current time"""
    import datetime
    return datetime.datetime.now().isoformat()

@server.tool("read_file") 
async def read_file(filename: str):
    """Reads content from a file"""
    try:
        with open(filename, 'r') as f:
            return f.read()
    except FileNotFoundError:
        return f"File {filename} not found"

# Start the server
if __name__ == "__main__":
    asyncio.run(server.start())

Connecting to an MCP Client

Most modern AI tools can connect to MCP servers. In Claude Desktop, you’d add this to your configuration:

{
  "mcpServers": {
    "my-first-server": {
      "command": "python",
      "args": ["path/to/your/server.py"]
    }
  }
}

MCP vs. Other Integration Methods

MethodProsCons
MCPStandardized, Interoperable, SecureNewer, Learning curve
Custom APIsFull control, FamiliarN×M problem, No standard
PluginsEasy setupVendor-specific, Limited

Security Considerations

🔒 Authentication & Authorization

  • Always implement proper authentication
  • Use role-based access controls
  • Validate all inputs

🛡️ Sandboxing

  • Run MCP servers in isolated environments
  • Limit file system access
  • Monitor resource usage

📊 Monitoring

  • Log all MCP interactions
  • Set up alerting for unusual activity
  • Regular security audits

The Future of MCP

As 2025 progresses, we’re seeing:

  • Enterprise adoption accelerating
  • IDE integration becoming standard
  • Security frameworks maturing
  • Performance optimizations rolling out

MCP is positioning itself as the HTTP of AI integration - a universal standard that every AI tool can understand.


Practical Next Steps

  1. Experiment: Set up a simple MCP server with file access
  2. Integrate: Connect it to your preferred AI assistant
  3. Expand: Add more tools and data sources
  4. Secure: Implement proper authentication and monitoring
  5. Scale: Deploy to production with proper infrastructure
  1. Read the official MCP specification
  2. Try the Python or TypeScript SDK
  3. Build a simple file server
  4. Connect it to Claude Desktop or another MCP client
  5. Gradually add more complex functionality

Conclusion

MCP represents a significant step forward in AI integration. Instead of every AI tool having its own integration method, we now have a universal standard that makes AI assistants truly interoperable with our data and tools.

Whether you’re building enterprise AI solutions or just want your AI assistant to access your local files, MCP provides a secure, standardized way to make it happen.

The protocol is still evolving, but the foundation is solid. Now is the perfect time to start experimenting and building MCP integrations for your projects.

Ready to give it a try? Start with a simple file server and watch your AI assistant gain real-world capabilities!