MCP Protocol: The Complete Developer Guide (2026)
Master the Model Context Protocol (MCP) — the standard for connecting AI assistants to tools and data. Learn architecture, transport modes, building servers, and best practices for Claude Code, Cursor, and any MCP client.
Alex Lopez
Founder, Snipara
The Model Context Protocol (MCP) is becoming the standard way AI assistants connect to external tools and data sources. Whether you're using Claude Code, Cursor, or building your own AI application, understanding MCP is essential. Here's the complete developer guide.
Key Takeaways
- MCP is a protocol, not a product — standardized way for AI assistants to access tools, resources, and prompts
- Works with Claude, Cursor, Windsurf, VS Code — and any MCP-compatible client
- Two transport modes — stdio for local servers, HTTP for remote/cloud servers
- Three primitives — Tools (functions), Resources (data), and Prompts (templates)
What Is the Model Context Protocol?
MCP (Model Context Protocol) is an open protocol developed by Anthropic that standardizes how AI assistants connect to external data sources and tools. Think of it as a universal adapter between your AI and the services it needs to access.
Before MCP, every integration was custom:
- Claude has its own plugin system
- ChatGPT has GPT Actions
- Cursor has custom integrations
- Every tool needs N different implementations
- Build one MCP server
- Works with all MCP-compatible clients
- Standardized authentication, errors, and capabilities
- One implementation, many AI assistants
MCP Architecture: The Three Primitives
MCP servers expose three types of capabilities to AI clients:
Functions the AI can call. Examples: search documentation, execute code, query a database.
Data the AI can read. Examples: file contents, database schemas, configuration.
Pre-built prompt templates. Examples: code review, summarize, explain.
Transport Modes: stdio vs HTTP
MCP supports two transport mechanisms for client-server communication:
| Feature | stdio (Local) | HTTP (Remote) |
|---|---|---|
| Use case | Local tools, file access | Cloud services, APIs |
| Latency | Sub-millisecond | Network dependent |
| Setup | Install locally, configure path | Just provide URL + API key |
| Security | Runs with user permissions | API key authentication |
| Examples | filesystem, git, sqlite | Snipara, Stripe, databases |
stdio Configuration Example
{
"mcpServers": {
"filesystem": {
"command": "npx",
"args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/docs"]
}
}
}HTTP Configuration Example
{
"mcpServers": {
"snipara": {
"type": "http",
"url": "https://api.snipara.com/mcp/your-project",
"headers": {
"X-API-Key": "rlm_your_api_key"
}
}
}
}MCP Clients: Where to Use MCP
These AI assistants and IDEs support MCP natively:
CLI with MCP add command
Settings > Developer > MCP
MCP in settings.json
Native MCP integration
config.json MCP section
Snipara extension adds MCP
Building Your Own MCP Server
MCP servers can be built in Python, TypeScript, or any language that supports JSON-RPC. Here's a minimal example:
Python MCP Server (FastAPI)
from fastapi import FastAPI
from mcp.server import Server
from mcp.types import Tool, TextContent
app = FastAPI()
mcp = Server("my-server")
@mcp.tool()
async def search_docs(query: str) -> list[TextContent]:
"""Search documentation for relevant content."""
results = your_search_function(query)
return [TextContent(type="text", text=results)]
# Mount MCP on /mcp endpoint
app.mount("/mcp", mcp.as_asgi())TypeScript MCP Server
import { Server } from "@modelcontextprotocol/sdk/server";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio";
const server = new Server({ name: "my-server", version: "1.0.0" });
server.setRequestHandler("tools/call", async (request) => {
if (request.params.name === "search_docs") {
const results = await searchDocs(request.params.arguments.query);
return { content: [{ type: "text", text: results }] };
}
});
const transport = new StdioServerTransport();
await server.connect(transport);MCP Best Practices
One tool per action. search_docs and get_doc are better thanmanage_docs.
The AI reads your tool descriptions to decide when to call them. Be explicit about inputs, outputs, and use cases.
Return helpful error messages. "Document not found: auth.md" is better than a 500 error.
If your tool returns content, let callers specify max tokens. Don't dump 100K tokens into a 4K context window.
Snipara: A Production MCP Server
Snipara is a context optimization MCP server with 43+ tools for querying documentation, managing memory, and coordinating multi-agent workflows. It's a good reference for building production-grade MCP servers.
Key Snipara MCP Tools
rlm_context_query — Semantic search with token budgetingrlm_remember / rlm_recall — Persistent agent memoryrlm_plan / rlm_decompose — Query planning for complex tasksrlm_swarm_* — Multi-agent coordination primitives