The Sixth Shim: When MCP Becomes a Middleware Factory

You started with one quick wrapper. Then another. Now you're running six bespoke shims between your MCP gateway and your servers, and nobody can explain the system without a whiteboard. This episode builds a taxonomy of shim patterns — transport translation, credential injection, tool filtering, schema coercion — and ruthlessly sorts which problems are generalizable infrastructure and which are server-specific one-offs that belong upstream. We name the real prior art, weigh the blast radius tradeoffs of consolidation versus independence, and give you a decision rule that prevents the seventh shim from ever being written. Episode #046353 — open it directly at myweirdprompts.com/046353