Why you'd want it
MCP is the protocol behind every server in this category: a server exposes tools, resources and prompts once, and any MCP client, such as Claude, ChatGPT, VS Code or Cursor, can discover and call them. Messages are JSON-RPC 2.0 over stdio for local servers or Streamable HTTP for remote ones, with OAuth recommended for remote auth. Official SDKs cover TypeScript, Python, C#, Go, Rust, Ruby, Java, Swift, PHP and Kotlin, so you can build a server or client in the language you already use.
Best for
- Exposing your own API or data to AI clients
- Building an agent host that connects to many servers
- Standardizing tool integrations across clients
Use it when
You want agents to reach an internal system or service, or you are building a client that should plug into existing MCP servers.
Skip it if
You only want to use existing servers; the spec and SDKs are for building servers and clients, so pick a server entry instead.