Model Context Protocol Server Design Patterns That Actually Hold Up

1. The Naive Wrapper Anti-Pattern: Why Directly Wrapping APIs Leaks Context Tokens When a service simply forwards a request to an external API and returns the raw response, it appears to be the easiest way to expose functionality to a language model. In practice this pattern discards the opportunity to control what part of the request or response participates in the model’s context window. The model receives the full payload, including authentication headers, pagination tokens, or internal identifiers that were never meant to be interpreted by the.