The Model Context Protocol (MCP) is an open standard for connecting agents to external capabilities. A service runs an MCP server that exposes tools, resources and prompts once, and any MCP-compatible agent (the client) can use them.

Why it matters

  • Before MCP, every agent framework had its own tool format, so each integration was rebuilt for each framework.
  • With MCP, an integration is built once and reused everywhere. The source compares this to USB for hardware: standardise the plug and the ecosystem grows on its own.
  • In practice, connecting an agent to an issue tracker, documentation or a database is often configuration rather than custom code.

Tools · Agent guardrails: content returned by MCP servers is data, not instructions.

Sources