THE TOOL REGISTRY

LEARNING GOALS By the end of this chapter you will be able to describe what a tool registry stores, how dispatch works, why typed handlers help, how on-demand discovery saves context, and how versioning and deprecation keep systems from breaking. THE REGISTRY AS A CATALOG Think of a hardware store with hundreds of tools hanging on a wall. Without a catalog and a labeling system, nobody could find the right wrench. An agent harness faces the same problem, and its solution is a tool registry. The tool registry is the catalog of available tools. It is a central list, kept by the harness, of every tool the agent could possibly use, along with everything the harness needs to know about each one. The registry has two big jobs. The first is to tell the model what tools exist, by giving it names and descriptions so the model can choose. The second is to help the harness run the chosen tool safely, by looking up its handler and its rules.