MCP: how Claude connects to the real world

2025

In 2024, Anthropic open-sourced the Model Context Protocol (MCP), a standard for connecting AI models to external tools, databases, and services.

Before MCP, if you wanted Claude to query your database or call an API, you had to write custom integration code. MCP standardized these connections, creating an ecosystem of "servers" that any MCP-compatible model could use.

The impact was immediate. Developers could set up a Claude environment with access to their GitHub repos, their databases, their monitoring tools, and their documentation, all through a simple configuration file.

This transformed Claude from a conversational AI into an agent that could take real actions: create pull requests, query production databases (read-only!), update tickets, send notifications, and coordinate complex workflows.

The open-source nature of MCP was deliberate. Anthropic wanted it to become an industry standard, not a proprietary lock-in. By making it easy for anyone to build MCP servers, they created a network effect that benefited the entire ecosystem.

By 2025, thousands of MCP servers existed for everything from Slack to Kubernetes to financial APIs.