Threat-Model an MCP Server as a Privileged API Gateway

An MCP server serves as a privileged gateway between an assistant and an API, accepting model-influenced requests. The focus is on which identities and resources the implementation can access. It's crucial to avoid granting full credentials to every tool, instead splitting read and write identities and using short-lived tokens. Server-side authorization must validate the caller and resource state while treating arguments as untrusted inputs.