MCP
Also called Model Context Protocol or MCP server
The Model Context Protocol: an open standard that connects AI apps to outside tools and data, such as files, databases, and design apps.
{
"mcpServers": {
"files": {
"command": "npx",
"args": ["-y", "@modelcontextprotocol/server-filesystem", "./docs"]
}
}
}Add an MCP server to this app with two tools: list_habits returns the signed-in user's habits, and check_in(habitId) marks one done for today. Use the official TypeScript SDK, validate every input, and require an API token on each request.
Paste into Layerwise or any AI coding tool.
MCP explained
MCP, short for Model Context Protocol, is an open standard that Anthropic introduced in November 2024. It defines one common way for an AI app to connect to outside tools and data. Each connection is an MCP server, which can offer tools the AI can call, resources it can read, and reusable prompts.
Without a standard, every AI app needs its own integration for every service. With MCP, a service publishes one server, and any AI app that supports MCP can use it, the way one USB-C port fits many devices.
A server runs on your computer as a local command or on the web over HTTP, and many apps list servers in a JSON file like the one below. Add only servers you trust: a server can read data and act for you, and its tool descriptions go straight to the model.
Related terms
All termsTool call
A request from an AI model to run a named action, such as reading a file, searching, or running a command, whose result goes back to the model.
AI agent
An AI model that works toward a goal on its own by planning, using tools, checking the results, and repeating until the task is done.
API
A set of rules that lets one program ask another for data or actions, usually by sending a request to a URL and getting JSON back.
Rules file
A file in your project, such as AGENTS.md or CLAUDE.md, with standing instructions that an AI coding agent reads at the start of every task.
Build it with Layerwise
Describe your app, watch it run in a live preview, and publish it with a database, storage, and sign-in built in.