What is MCP?One plug for every app. Your rules not included.

What MCP is, in plain English

Remember when every phone had its own charger? Then most of them moved to USB-C, and one cable fits them all. The people behind MCP use the same picture: it's a common plug between AI assistants and the apps you use.

Before MCP, each AI company had to build its own link to each app, one pair at a time. With a shared standard, an app maker like Intuit or HubSpot builds one connection, and any assistant that speaks MCP can use it. Your assistants call these links connectors, or apps.

You don't need to install or understand MCP to use it. In your assistant's settings it shows up as a list of apps, each with a Connect button and a sign-in to that app.

What is an MCP server?

You'll see this phrase a lot. Despite the name, it simply means the app maker's side of the plug: the piece that tells an assistant what it can look up or do in that app. In this guide we just call it a connector.

Who created it, and who has adopted it

• November 2024: Anthropic, the company behind Claude, introduces MCP as an open standard anyone can use.
• October 2025: OpenAI builds its apps in ChatGPT on MCP.
• December 2025: Anthropic hands MCP to the Agentic AI Foundation, a new group under the Linux Foundation set up with Block and OpenAI, and backed by Google, Microsoft, Amazon Web Services, Cloudflare and Bloomberg. At the time, Anthropic counted ChatGPT, Gemini, Microsoft Copilot and others among the products using it. Google announces official MCP support for its own services the next day.
• Today: Microsoft Copilot uses MCP for its live connections to outside apps like HubSpot, Gmail and Xero.

So no single AI company owns it. That matters, because it means the connection your app maker builds isn't tied to one assistant.

What a connector does and doesn't do

A connector:

• signs in to the app as the person using it, with their own login
• sees only what that person's account can already see
• looks things up when someone asks: a report, a customer, an open deal
• can make changes, like drafting an invoice or updating a contact, only if the app maker built that in and your settings allow it

A connector doesn't:

• decide anything; the assistant and the person asking do
• know your terms, your policies or which numbers matter to you
• fix messy data or loose permissions in the app itself

Is MCP itself safe? The standard is only the plug. How safe a connection is depends on three things: what the app maker lets the connector do, what your assistant's settings allow and what each person's login can reach. Check all three.

Two real examples

Claude and QuickBooks

Intuit makes its own QuickBooks connector for Claude. As of October 2026 it's for US customers with QuickBooks Online and some other Intuit plans. It can read reports like profit and loss and cash flow, and it can create and send invoices and estimates. Intuit says it asks for your confirmation before deleting anything, and that new invoices appear in QuickBooks straight away, so you should check them.

ChatGPT and HubSpot

HubSpot makes a connector for ChatGPT that works on any HubSpot plan. It can read contacts, deals, tickets and email history, and create or update records up to 10 at a time, but not delete them. Unless you're a super admin or have marketplace access in HubSpot, a super admin has to approve it before you can connect. HubSpot's similar connector for Claude also can't delete, and HubSpot recommends setting it to ask for approval before every update.

Why it matters to you

• You're less locked in. If you switch from one assistant to another, the apps you rely on are likely to work with both.
• More of your apps are reachable. App makers build one connection instead of one per assistant, so more of them do it.
• The app maker often builds it. When Intuit or HubSpot makes the connector, it follows their own rules about what can be read and changed.

What it doesn't solve

MCP answers "can the assistant reach this app?" It doesn't answer "should it, for this person, right now?" That part is about how your business works.

• Your definitions. Ask "who owes us money?" and a connector can fetch unpaid invoices. It doesn't know you give trade customers 60 days, or that one client is on a payment plan.
• Your roles. It follows each person's app login. If everyone signs in as the owner, everyone's assistant sees the owner's numbers.
• Your approvals. Assistants can ask before making a change, but who is allowed to say yes to a refund or a discount isn't part of the standard. Someone has to decide, write it down and set it up. Our guide to keeping a person in the loop covers how.
• A record of who asked what. Some assistants and apps keep one. It isn't guaranteed, so check.

Questions to ask before you connect anything

1. What can it read? All customers, or only the ones this person handles? Payroll? Bank details?
2. What can it change? Can it create, update or delete, and in which records?
3. Who approves changes? Does it ask every time, and can each person switch that off?
4. Is there a record? Can you see later who asked for what and what changed?
5. Who built it? The app maker, the AI company or someone else?
6. How do you switch it off? For one person when they leave, and for everyone at once.

If you can't answer one of these, leave that connection off until you can. Most business plans let an admin allow look-ups and block changes, so you can start there and add changes later.

How we use it

MCP is how we connect your apps, not what we sell. What we sell is everything around it: learning how your team works, writing down your terms and rules, deciding who can ask for what and what always needs a person, and training your team. In every setup, everyone has their own login and sees only what their role allows, there's a full history of every request, and nothing changes in your apps unless a person says yes. It works with whichever assistant you use. See the apps we work with, or book a free 30-minute call.