TL;DR: We built a one-shot HTTP worker that talks to Notion through MCP. Version one worked. Version two got cheaper and more readable, then failed in a new way. The harness was fine. The tool surface, the model, and the prompt were not the same problem, and we kept treating them as one. We keep seeing the same pitch: put an agent in the cloud, give it tools, let it live in Slack, let it remember you. That is a product. It is not the product we needed. We needed something dumber and mor...