Journal · Developers
MCP explained, and what it does not give you
A useful, boring piece of plumbing that is regularly oversold. Worth understanding precisely, because the overselling is usually about portability.
What is the Model Context Protocol? An open standard for connecting AI assistants to external tools and data sources through a common interface, so a capability built once can be reached from several assistants rather than integrated separately into each.
Before a standard existed, every assistant had its own way of exposing tools, and every integration was rebuilt per platform. MCP defines a common protocol: a server exposes capabilities, a client connects, the assistant can call them. That is genuinely useful and genuinely unglamorous.
What it gives you
- One integration, several clients. Build the server once.
- A defined boundary. What is exposed is what you chose to expose, with scope you control.
- Reach into the tool people already use, instead of asking them to open another one.
What it does not give you
This is the part that gets skipped in marketing copy.
- It does not make you model-independent. If your orchestration runs on your server, that orchestration is still built against particular model behaviour. Switching models is a migration, not a dropdown.
- It does not control the reasoning. The host model decides how to use what you expose, and how well it does that varies.
- It does not solve multi-turn latency. A deliberation with several internal rounds inside a chat client is slow, and the client controls the experience.
- It does not make the client the product. If the work happens server-side, the MCP surface is an access facade. That is a reasonable architecture. It is not independence.
Portability comes from the format your data leaves in, not from the protocol it arrives through.
The honest version of the portability claim
What genuinely survives a change of model is a record in an open format that you can export and read without our software. That is a property of the data, and it is testable: ask any vendor for an export and see what you get.
Five Peers editorial note. Sources named in the text.
The record exports whether or not the connector is open.
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