THE STANDARD
What the Model Context Protocol is.
MCP is the open standard that lets an AI assistant use an outside tool. It is how your Twin is read.
Last verified
What is the Model Context Protocol?
An open standard that lets an AI assistant use an outside tool. Instead of each assistant inventing its own plugin system, one protocol describes how a tool announces what it can do and how the assistant calls it.
Who controls it?
No single company. It was donated to the Agentic AI Foundation under the Linux Foundation in December 2025.
Which assistants support it?
Support varies by assistant and by plan. The dated position for each is listed below.
Where it came from
The Model Context Protocol was released as an open standard around 25 November 2024 under an MIT licence.
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MCP was donated to the Agentic AI Foundation under the Linux Foundation on 9 December 2025, co-founded with Block and OpenAI, with platinum members including AWS, Google, Microsoft, Cloudflare and Bloomberg. It is no longer any single company's protocol.
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Anthropic's 9 December 2025 ecosystem update cited more than 10,000 active public MCP servers and more than 97 million monthly SDK downloads across Python and TypeScript.
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Who supports it, by plan
Free with one connector, Pro, Max, Team and Enterprise.
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Custom connectors require Developer Mode, which OpenAI lists as available on Plus, Pro, Business, Enterprise and Edu accounts on the web. OpenAI's own documentation is currently inconsistent about write actions: its developer guide describes full read and write support on those plans, while its help centre article describes write actions as a beta limited to Business, Enterprise and Edu. These appear to be two different mechanisms sharing a name. Check in your own account before relying on write actions.
Verified . Primary source: OpenAI's own documentation, which is self-contradictory on this point between its developer guide and its help centre article.
Pro, Max and Enterprise.
Perplexity's own documentation has been inconsistent about availability, so check in your account.
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All plans including free, launched 2 September 2025.
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Not verified. We have not been able to confirm this from xAI's own documentation.
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No clear route for a user to add a custom connector.
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No clear route for a user to add a custom connector.
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Why it matters for memory
A memory layer is only useful if the assistant you happen to be using can read it. MCP is what makes that possible without a separate integration for every assistant. How to connect your Twin.