What Are MCP Servers?
An MCP (Model Context Protocol) server is a lightweight process that gives Claude Code access to external tools and data sources. The Model Context Protocol is an open standard that defines how AI assistants communicate with tool servers. When you install an MCP server, Claude gains new capabilities — like querying your PostgreSQL database, managing GitHub issues, or searching documentation — all through natural language.
How MCP Servers Work
MCP (Model Context Protocol) is an open standard created by Anthropic that defines how AI assistants communicate with external tool servers. When you install an MCP server, it runs as a separate process — either locally on your machine or on a remote host — and exposes a set of tools that Claude Code can call.
For example, a PostgreSQL MCP server connects to your database and provides tools like "run_query", "list_tables", and "describe_schema". When you ask Claude to check your database, it uses these tools to get real data — no copy-pasting required.
MCP servers communicate over a standardized protocol, which means any MCP-compatible client can use any MCP server. This makes the ecosystem interoperable: a server built for Claude Code will also work with other MCP-compatible tools.
Types of MCP Servers
MCP servers connect Claude to virtually any external system. Here are the most common categories:
Database Servers
Connect to PostgreSQL, MySQL, MongoDB, SQLite, and other databases. Query data, inspect schemas, and manage migrations directly through Claude.
Platform Integrations
GitHub, GitLab, Jira, Linear, Slack, and other platforms. Manage issues, pull requests, messages, and project boards from your editor.
File & System Access
Extended filesystem operations, remote file access, cloud storage (S3, GCS), and system monitoring tools.
Search & Knowledge
Web search, documentation search, vector databases, and knowledge base servers. Give Claude access to information beyond its training data.
API & Web Services
REST API clients, GraphQL endpoints, webhook managers, and third-party service connectors for everything from payment processors to email services.
Most Popular MCP Servers
These are the top 5 most-used MCP servers across the Claude Code community.
Everything
Model Context Protocol Servers
by modelcontextprotocol
Fetch
Model Context Protocol Servers
by modelcontextprotocol
Git
Model Context Protocol Servers
by modelcontextprotocol
Memory
Model Context Protocol Servers
by modelcontextprotocol
Sequentialthinking
Model Context Protocol Servers
by modelcontextprotocol
How to Install an MCP Server
Most MCP servers can be added to your Claude Code configuration with a single command:
claude mcp add <server-name> -- npx <package-name> Some servers require configuration like API keys or database connection strings. Each server's detail page on Claude Bazaar includes its specific setup instructions.
MCP Servers vs. Skills vs. Plugins
MCP servers provide Claude with access to external data and systems through a running process. Skills are static instruction sets that teach Claude specific tasks. Plugins bundle multiple tools together.
Use an MCP server when Claude needs to interact with an external system in real time — databases, APIs, platforms. Use skills when you want Claude to follow a specific process or workflow. Use plugins when you want a complete toolkit in one install.
Finding the Right MCP Server
With 775 MCP servers available, browse by category on our Explore MCP Servers page, or check the Top MCP Servers rankings. You can also search by tag to find servers for specific platforms and technologies.