Our solutionInstead of loading all tool definitions upfront, the Tool Search Tool discovers tools on-demand. Opus 4 improved from 49% to 74%, and Opus 4.5 improved from 79.5% to 88.1% with Tool Search Tool enabled. How the Tool Search Tool worksThe Tool Search Tool lets Claude dynamically discover tools instead of loading all definitions upfront. When to use the Tool Search ToolLike any architectural decision, enabling the Tool Search Tool involves trade-offs. They're complementary: Tool Search Tool ensures the right tools are found, Programmatic Tool Calling ensures efficient execution, and Tool Use Examples ensure correct invocation.