@runbit/tool

First-class, typed tools with clear validation errors.

npm install @runbit/tool

import { tool } from "@runbit/tool";
import { z } from "zod"; // any schema with .parse works — zod is optional

const weather = tool({
  name: "weather",
  description: "Get the weather for a city.",
  parameters: { type: "object", properties: { city: { type: "string" } }, required: ["city"] },
  input: z.object({ city: z.string() }),
  run: ({ city }) => `sunny in ${city}`,
});

• parameters is the JSON schema a model uses to call the tool.
• input is any object with a parse (zod-compatible) — invalid input throws a RunbitError naming the tool.
• createToolRegistry(tools, getContext) runs tools and emits tool:start / tool:end / tool:error.

Part of Runbit — the AI Runtime. Everything executes through one small, event-driven runtime; agents, workflows, RAG, and observability are packages on top.

• Umbrella: @runbit/runtime
• License: MIT