Plugins/MCPs learning experience

Witnessing a friend who's less skilled at technology and AI burn through 5 hours of usage in right about 2 hours created a situation where we had to pause and figure out what was wrong.

It did not appear she is doing anything extreme: reading some websites, building some content on what was found, and a few other things.

When it gave her the warning, we were a bit surprised.

Turns out, a couple of days before, when setting up her account with Claude and installing Claude Desktop, at some point Claude asked, "Do you want to install plugins for sales and plugins for marketing?" and something else. Being a small business owner with little understanding of what that means, she simply checked both boxes for sales and marketing.

This triggered Claude desktop to install a series of MCP serversbconnections approximately 25 to 30.

Many of which were services you would probably never use. These appeared to be standard Anthropic plugins. Nothing seemed out of the ordinary.

Well, except for the usage that just kept climbing to the degree that, before we could fix the problem, she had added credits to the tune of $60 or $70.. Just to get through the tasks that she needed to do .

When we realized this, we instructed Claude to explain how to remove these because I had seen in other situations where removing the plugin did not necessarily remove the underlying infrastructure, like an MCP configuration.

That said, this time they were lucky, and just removing the plugins did ultimately remove these extra MCPs, but the thing that's important to know

Is it that every MCP listing, whether you're authenticated to it or not, costs tokens to maintain in your session?

Based on this experience, I'm not suggesting anyone install the straight-up plugins. Tell them to only ever install an MCP or, potentially, a plugin, so that you know exactly what it's installing and whether you're going to need those things or not. Just suggest not realizing the impact.

And it's not really in Anthropic's best interest to tell them the situation, because when the result of not knowing triggers the ability to earn double the tokens or get a client to pay more for extra tokens to finish jobs. We calculated that the extra MCPs configured and never used, not even authenticated, were costing approximately 1,500 to 2,500 tokens across the board.

Check your MCPs:

- Use /status

- Use claude-spend

- Use /doctor to evaluate if you're carrying around stagnant and unnecessary MCPs that are costing you tokens on every call.

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Plugins/MCPs learning experience