An MCP Server exposes data sources or tools to AI assistants via Model Context Protocol. MCP servers run on the customer's infrastructure (or hosted by the agent platform); the AI assistant connects + uses the exposed capabilities.
Common MCP server patterns in 2026:
- Database query MCP server (read-only access to internal data)
- Filesystem MCP server (read/write access to project files)
- API gateway MCP server (wrap internal APIs for agent use)
- Knowledge-base MCP server (search documentation, runbooks, wikis)
The architectural value: write the MCP server once + every MCP-compatible agent (Claude Code, Cursor, custom orchestrators) can use it. Before MCP, every agent framework needed its own integration. See our Enterprise AI Agent Architecture.