What Is MCP (Model Context Protocol)?
If you have ever wished Claude could read a file, search your notes, or remember something from yesterday, you have wished for MCP without knowing the name.
Model Context Protocol, or MCP, is a shared language that lets an AI app talk to outside tools. Instead of every tool inventing its own way to plug into Claude, ChatGPT, or Cursor, they all speak MCP, so any tool that speaks it can connect to any app that speaks it.
If you want memory that follows you across the tools you use, this is the part that makes it possible. Skein offers your memory through MCP, and this page explains what that means for you.
Related: OAuth vs API Keys covers which tools can actually connect, and Best AI Memory Tools in 2026 shows where everything fits.
The short version: USB-C for AI tools
Think of MCP as USB-C for AI tools.
Before USB-C, every device had its own cable. MCP does for AI tools what one standard plug did for everything else: any tool can connect to any app, without a custom adapter for each pairing.
- The app you use (Claude, ChatGPT, Cursor, VS Code) speaks MCP on one side.
- A tool (a memory store, a database, a calendar) speaks MCP on the other.
- You connect the two, and the app can now use the tool.
You do not download "MCP" or install it as a product. You connect MCP tools to the AI apps you already use.
Why this matters for memory
Memory is the kind of thing you want to keep for years. If your memory lived inside one company's private system, you would be betting that one company stays on top forever, and that it never changes the rules on you. That is a shaky place to keep something you care about.
MCP is not owned by any single company. By early 2026 it had become shared infrastructure the whole industry builds on, the way many companies build on standards like Wi-Fi or USB rather than one vendor's private connector. Major AI apps support it, and it is governed in the open rather than behind one company's closed roadmap.
For you, that means a memory built on MCP is not trapped inside one chat app. It can serve Claude today, a different app next year, and whatever you switch to after that.
What MCP lets Skein do
Skein is a memory you can reach from every AI app you connect. Because it speaks MCP, those apps can save a thought, search what you have stored, and pull back the right context while you work, with you in control of what each one is allowed to do.
Without a shared standard, "one memory, every app" would mean building a separate custom connection for each app, forever. MCP is what turns that into something you can just switch on.
A word on safety
Because MCP makes it easy to connect tools, it also makes it easy to connect the wrong tool, or to feed an AI app something it should not trust. Security researchers have catalogued dozens of ways these connections can be abused, from sneaking hidden instructions into a tool's output to tricking the approval step into granting more access than you meant.
This is not a reason to avoid MCP. It is a reason to choose memory tools that treat anything coming in as suspect until proven safe. A few things to look for:
- It controls what each connected app can read and write, so one app cannot quietly reach everything.
- It connects through a proper approval screen you can revoke, not a secret pasted into a link. (Why this matters.)
- It is careful about credentials, so a password or key you mention by accident does not get quietly stored.
Skein lets you set what each connected app can read and write, and connects through the approval-and-revoke flow rather than a pasted secret. On Pro and Max, it scans captures for likely secrets and holds them aside until you resolve them. You can also share one namespace, read only, with someone you trust. See Sharing a Namespace in Skein.
Where MCP stops
MCP handles how apps and tools talk to each other. It does not yet settle what a "memory" means from one app to the next, so things like how memories are exported, where they came from, and how they are organized still vary between products.
That is the gap newer efforts like Portable AI Memory aim to close, sitting on top of MCP to make your memories themselves portable, not just the connection. Skein is building toward that. MCP is the connection layer that works today.
The bottom line
MCP is the standard that lets your AI tools share one memory instead of each starting from scratch. Skein uses it so the apps you already use can draw on the same memory, without becoming one more app you have to open every day.