What is MCP Server
MCP(Model Context Protocol)是 Anthropic 提出的开放Protocol,用于标准化 AI 模型与外部工具、数据源之间的通信方式。MCP Server 是实现该Protocol的服务端程序,为 AI Clients提供工具调用能力。
Core Concepts
MCP defines three roles:
- Host(宿主):The application that users interact with directly, such as Claude Desktop, Cursor, etc.
- Client(Clients):The MCP protocol client inside the Host, responsible for communicating with the Server.
- Server(服务端):Programs that provide specific tool capabilities, such as file system access, database queries, API calls, etc.
A Host can connect to multiple MCP Servers simultaneously, each providing different tool sets.
Differences Between MCP Server and Regular Plugins
| Comparison | MCP Server | Regular Plugins |
|---|---|---|
| Protocol | Standardized JSON-RPC protocol | Platform-specific private APIs |
| Reusability | One Server can be used by multiple clients | Usually only works with specific platforms |
| Runtime | Independent process, communicating via stdio or HTTP | Usually runs within the host process |
| Language | Any language (Node.js, Python, etc.) | Limited to platform SDK |
| Security Boundary | Process isolation, controllable permissions | Usually shares host permissions |
How It Works
The MCP communication flow is as follows:
- When the Host starts, it launches MCP Server child processes based on the configuration file.
- The Client establishes a JSON-RPC connection with the Server via stdio (standard input/output).
- The Server declares its available tools and resources to the Client.
- During user-AI conversations, the AI calls Server-provided tools as needed.
- The Server executes operations and returns results, which the AI integrates into its response.
用户 → Host(Claude Desktop) → Client → MCP Server → 外部服务/文件系统
↓
Returns execution results
What Can MCP Server Do
- Read/write local file system
- Execute database queries
- Call third-party APIs (GitHub, Slack, Notion, etc.)
- Run Shell commands
- Search and scrape web content
- Manage calendars and emails
Important Notes
- MCP Server runs as a local process with the system permissions you grant. Always verify the permission scope before connecting.
- Different Servers have different risk levels. Read-only file tools are low risk, while those that can execute commands or access the network are higher risk.
- The MCP protocol is still rapidly evolving. Configuration formats may change with client versions.
FAQ
- Is MCP proprietary to Anthropic?
- MCP is an open protocol with open-source specifications and SDKs. Any AI client can implement MCP support. Currently Claude Desktop, Cursor, Windsurf, and others support it.
- Do I need programming skills to use MCP?
- Basic usage only requires editing JSON configuration files, no coding needed. However, understanding command-line operations and environment variables is helpful.
- Does MCP Server auto-update?
- No. MCP Servers run via npx or uvx will pull the latest version, but locally installed ones need manual updates. We recommend regularly checking official repository changelogs.