What is an MCP server? Plain-English guide

What MCP and MCP servers are, in plain words: how to add one to Claude Code or Cursor, how to stay safe, and how your agent deploys apps through one.

MCP, the Model Context Protocol, is an open standard that lets an AI app such as Claude Code or Cursor use outside services: read your GitHub issues, click through a website, or put your code online. An MCP server is the service on the other end. It offers the AI a list of actions it may take, once you approve it. This page explains both in plain words, shows how to add one safely, and shows how aidrop.it’s server lets your agent deploy what it builds in the same conversation. Trying aidrop.it is free for 7 days; keeping an app online starts at $5 a month.

What you will have at the end

A clear picture of MCP, MCP servers and tools.
The steps to add a server to Claude Code or Cursor, and to take access back.
If you want, your agent connected to aidrop.it, ready to put apps online.

Words you will meet

AI app: the program you chat with, such as Claude Code, Cursor, Claude or ChatGPT. MCP calls it the host.
MCP server: a plug-in service that gives the AI app new abilities. It runs on your computer (local) or on the internet (remote).
Tool: one action a server offers, like “create an issue” or “build my app”. The AI decides when to use it; many apps ask you first.
Sign-in screen: a browser page where you approve what a remote server may do, such as only look or also make changes, instead of copying a password.

How it works

Your AI app connects to each server you added and asks what tools it has. When the model decides a tool would help, the app calls it and passes the result back into the conversation. A remote server is reached by its web address, and you sign in once in your browser. A local server runs on your own computer. The official MCP architecture overview has the details. Well-known servers include GitHub for issues and code, Microsoft’s Playwright for clicking through web pages, Sentry for error reports, and Notion for your notes.

Adding a server

In Claude Code, you add a server by its address with one command from Claude Code’s MCP guide, then open the MCP menu inside Claude Code and sign in. aidrop.it installs as a plugin instead; the Quickstart has the two lines to paste.

In Cursor, open Cursor’s settings, choose MCP and add a new server (Cursor’s MCP guide). Name it aidrop and paste this address: https://aidrop.it/mcp. If Cursor opens a settings file instead of a form, ask Cursor’s agent to add a server named aidrop with that address for you. Then click the login link next to the server and approve the sign-in.

Staying safe

An MCP server acts as you, so adding one is like handing someone a key.

Connect only servers you trust, published by the service’s own maker.
Approve only what you need. Read-only access is enough for many jobs.
Keep confirmations on for anything that changes or deletes.
Be wary of hidden instructions in pages or documents the AI reads. Give your agent a password or key only when the task needs it, and only once, so it can store it.
Take access back when you are done: remove the server from your AI app and revoke it on the service’s side.

For an agent that changes a live app, the roles, confirmations and backups that keep a mistake from becoming a loss are in how to stop your AI agent from deleting your project.

Example: how your agent deploys through aidrop.it

Connected to aidrop.it, your agent does the whole job in one conversation. It creates a project, saves the code in a repository, builds it and starts it. If the app does not run, it reads the error log, fixes the code and builds again. Then it gives you the link. It can also stop the app, go back to an earlier version, connect your domain and create a database. The whole path from first build to rollback is in the life of an app on aidrop.it. aidrop.it never writes code itself; your agent writes it on your computer. Teammates and their roles are managed in the dashboard, not by the agent.

The sign-in screen asks you to pick your Team and approve two permissions: to see your apps, and to build and run them. In each project the agent can do what your own role allows. It is told to ask you before deleting anything, and most deletions need an explicit confirmation. A Team admin can see and take back every connection on the Connected apps page, found under Management in the dashboard’s menu. Every tool the agent can use is listed in the full MCP reference, and What is an MCP deployment platform? explains the idea at more length.

The “agent” here is the coding agent you chat with. If you want an AI agent that runs by itself around the clock, answering people or doing tasks, put your AI agent online.

Say this to your agent

Use the aidrop.it MCP server to put this project online.

List my aidrop.it projects first and use the right one, or create one if I have none. Read aidrop.it's runtime rules before changing code, and follow them. If the app needs a database, check whether the project has one and ask me before creating it.

Tell me before the first deploy that the link will be public. Save the code to an aidrop.it repository, build it, check that it runs, fix it if it does not, and give me the link.

Secrets: ask me for each password or key the app needs, store each one with project_secret_set under a clear name, and list those names in required_secret_names when you build. Never print a value back to me, and never write one into code, the repository, a commit or a log.

Report back: the link, what you built, and anything I still need to do.

Check that aidrop.it is connected

In your AI app’s MCP list, aidrop.it shows as connected.
Ask your agent “Which aidrop.it projects do I have?” It lists them.

When the connection fails

What you see	What to tell your agent
The server shows as not connected	No need to ask: open your app’s MCP settings and sign in again.
The sign-in page never opens	Use an app that supports signing in to remote servers, such as Claude Code, Codex or Cursor.
The agent says it has no aidrop.it tools	“Reconnect the aidrop.it server and list my projects again.”

FAQ

What is the difference between MCP and an API?

An API is a door into one service, built for programmers, and every service’s door is different. MCP is a shared plug shape for AI apps: any app that speaks MCP can use any MCP server without custom code. Many MCP servers are built on a service’s API and turn its actions into tools an AI understands.

Is MCP only for Claude?

No. Anthropic introduced MCP as an open standard, and many AI apps now use it, including Claude Code, Claude, Cursor, VS Code and ChatGPT. A remote server can work in all of them, though each app adds it its own way.

Are MCP servers safe to use?

As safe as the service behind them and the access you grant. A server can do whatever your approved permissions allow, as you. Use official servers, approve the least access that does the job, keep confirmations on for changes, and revoke access you no longer use.

What is an MCP deployment platform?

It is a hosting service your AI agent runs directly through MCP, instead of you clicking through a dashboard. aidrop.it is one: the agent creates the project, builds the code, reads the errors and gives you the link, all in the conversation where it wrote the app. To try it, start free: a 7-day trial, no card; after that, Starter costs $5 a month.

What is an MCP server? A plain-English guide