MCP server
Definition
An MCP server is a service that offers tools to an AI agent via the Model Context Protocol - such as "look up order", "issue refund" or "delete record". AI clients like ChatGPT or Claude connect to the server, see the tool list and invoke the tools on the user's behalf.
MCP servers are appearing everywhere: companies like Scalable Capital or ElevenLabs open their products to agents this way, and teams generate MCP servers from existing API descriptions. The server defines what is technically possible - not what should be allowed.
That is where a control layer comes in: a transparent proxy in front of the MCP server records every tool call and can hold critical ones until a human approves them - without changing the server itself.
Related terms
tokyn.trail puts tracking, rules and human approvals in front of your MCP server - in 10 minutes, no code changes.
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