Porting a Legacy .NET REST API to WebMCP: Architecture, Results and Pitfalls

A DEV Community article examines moving an ASP.NET Core REST service that calls Azure OpenAI and vector search over to a WebMCP-backed endpoint. The author explains that single-shot request/response designs drive up latency and token costs, since prompts and retrieved data are resent in full on each call. A case study of a catalog API handling 1.2 million requests per day reported high latency, rising token spend, and timeouts at peak load. The piece weighs WebMCP's benefits, such as lower token usage, server-side session state, and per-tool observability, against drawbacks including a single entry point, a dependency on a session store, and harder debugging. It closes with guidance on when WebMCP suits a workload better than REST, based on traffic mix, statefulness, team skills, and cost sensitivity.