What the Heck is MCP?

I've been following the MCP hype for months without really getting it. Why does this standard matter? What's all the fuss about? The specification was confusing, the documentation was hard to follow.

Then a couple days ago, I decided to just try it. I installed a text messaging MCP server, connected it to Claude Desktop, and asked Claude to text my friends a summary of some research I'd been doing. When I saw the message go through, it finally clicked. I could change the world around me with Claude. It was no longer just a research tool.

MCP turns the LLM into a universal interface for all your apps and services. So you can do something like…"text John a high level summary of the 2025 income statement in my downloads folder" and the LLM will know to find the document, summarize it, figure out John's information via some messaging MCP, and then send that summary to John. If you take a second to think about all the moving pieces, that's pretty cool.

I don't know if you have ever seen an AI assistant in an app? Like the ones in database or analytics apps, you can ask a question in natural language and it will convert it into whatever query language the app uses. MCP inverts the responsibilities. Rather than the app dev integrating with the model, the model is integrating with the app. This is cool for two main reasons:

1. The foundation models are much better at prompting, so they will do a better job than the app will at converting natural language to appropriate queries.
2. Your customers can connect your app to the rest of their workflow. For example, let's say you stored inventory data. They could ask Claude to store the relevant inventory data from an invoice on their computer. Literally, they could go "store the relevant info from file july_inventory.pdf in InventoryManagementCo" and Claude would find the file, use its vision (VLMs are super powerful btw, more on that in another post) to extract the data, and then use your app's MCP API to upload the data.

But there are serious cons to MCP that are worth talking about:

1. At the moment, it's HIGHLY insecure. For that reason, I would exercise a lot of caution when using MCPs.
2. Your users stop using your app. If that's important to you, e.g., if you're in the ads business, this will kill your business.
3. Your app risks losing its moat. Think about it…If I have unfettered access via natural language to your inventory management app and the LLM can also code, then…
   • "pull the latest data from InventoryManagementCo"
   • Hook into a database MCP
   • "Ok add a table with columns from the keys of the data from InventoryManagementCo"
   • "move all data from inventorymanagementco to neon db"
   • "store relevant info from august_inventory.pdf in my neon db"

That being said, MCP is still pretty exciting.

I'm especially excited about MCP connecting to the physical world. There's already an MCP that lets you control your smart home - imagine asking Claude to turn off all the lights when you're already in bed, or having it adjust your thermostat based on tomorrow's weather forecast.

I think it'll be really powerful for enterprises too. Employees could connect to internal MCP servers through their Claude instances, instantly accessing company databases, analytics tools, and workflows.

What really gets me excited is that MCPs aren't limited to basic CRUD APIs. You can build MCPs that enable agentic behavior. Imagine an MCP server that spawns manages agents and long running workflows across multiple systems.

I won't really go into the technical details. There are plenty of resources out there, but honestly, the MCP specification is still in early phases so a lot of things just don't make sense at the moment. The term "Model Context Protocol" itself is confusing. The most important technical thing IMO is that MCP is an API for programmatically exposing "tools" for the model to call.

I'm excited to see how MCPs evolve. Companies are starting to release MCP servers, and it'll be interesting to see how this all plays out. Will every SaaS eventually have an MCP? Will we see MCP registries like npm? The potential is wild, and we're just at the beginning.

Here's a remix I made for getting this far: