Model Context Protocol (MCP)
Every tool.
Zero glue.↘
What problem does MCP solve?
Before MCP, every AI app needed its own bespoke connector to every tool. With N apps and M tools that's N×M one-off integrations to build and maintain, and a connector for one app was useless to the next.
MCP (Model Context Protocol) defines one common protocol both sides speak, so each tool exposes itself once as a server and each app speaks MCP once as a client. The N×M tangle collapses to a tidy N+M, and anything new instantly works with everything that already exists.
actually expose?”
→ Tools, resources, and prompts,
discovered on connect.
What are the two roles in MCP and how do they talk?
There are two roles. The host app, such as Claude Desktop, an IDE, or a coding agent, runs an MCP client.
The tool or data source runs an MCP server.
They exchange small structured messages using JSON-RPC, either over standard input/output for a local server or over HTTP for a remote one. When the client connects it first does a handshake to learn what the server offers, so neither side has to be hard-coded with knowledge of the other.
host app
handshakes
server offers
or data source
(stdio or HTTP)
client's calls
What three things does an MCP server expose?
Three kinds of things, all discovered automatically on connect. Tools are functions the model can call, like send_email or query_database.
It's the same idea as ordinary tool calling, standardized.
Resources are read-only data the app can pull in as context, like a file's contents or a database row. And prompts are reusable templates the server suggests, such as a ready-made "summarize this ticket" instruction.
This is a small sample.
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