Glossary · Phase 1 · Building with LLMs
MCP host
The AI app, such as a chat app or code editor, that connects to MCP servers and lets the model use their tools.
Try it now
Send each step in order. Note that JSON-RPC errors come back with HTTP 200: the error is inside the body, under "error".
Learn it properly
Model Context Protocol · A standard way to plug tools and data into any AI app. About 25 minutes.
Other terms from the same lesson
- JSON-RPC: A simple way for one program to ask another to run a named command, with the request and reply written as JSON. MCP uses it.
- MCP: Model Context Protocol: a standard way to plug tools and data sources into AI apps.
- MCP server: A small program that offers tools or data to AI apps through MCP, such as one that reads your calendar.
Never trained an AI?
Teach a small one to write, right in your browser. It takes about 20 seconds and needs no account.