Your Agent Pays a Tax on Every Tool It Never Calls

Most agents are billed for tools they don't use. Not once — on every single turn. The mechanics are simple enough that it's easy to miss. When you give a model a set of tools, the full JSON schema for every tool goes into the request. Names, descriptions, parameter types, enum values, nested objects, the lot. The model reads all of it, picks one, and calls it. Next turn, the whole catalog goes over the wire again, because the API is stateless and the tool list is part of the request. With eight…